(I'm going off of memory of dozens of conversations I've had with people about this, so some of the historical facts may not be 100% accurate)
Before Eos/Ion/Congo, there were the Obsession II and Express(ion) consoles in ETC's product line. At their time, those consoles were "adequate" at programming automated fixtures. Then ETC developed Congo with Avab. Congo was based on Avab's Pronto console, and Avab had a large enough presence in Europen that when Congo came out, European programmers felt very comfortable in front of them. Us Americans balked at the syntax and a lot of people never got past that, but for the European market there was nothing unnatural about it.
In North America, everyone was loving their Express(ion)/Obsession consoles. Idea/Acclaim/Vision -- all of ETC's earlier consoles looked much like the Express(ion) consoles, so by the time Express rolled around, lots of people in the United States were already hooked on that style of console. Even with the Strand's older (and newer consoles), they were a lot like Express in that any way you spoke to the console, the console would do what you expected it to. You could speak (and type in) the commands in a half-dozen different ways, but so long as your sentence made grammatical sense, there was a good chance you'd get what you want.
Congo was ETC's major diversion from Express-style consoles. Congo was fundamentally more different from Express/Obsession than Express from the consoles Fred was building with his brother out of their parents' garage. It was unlike any console ETC had ever worked on.
It was ETC's jump big jump into controlling moving lights. Congo was leagues ahead at that time from anything else ETC and their competitors offered. If you wanted a Hog, you could go that route, but most Hog programmers will tell you they aren't great consoles for handling conventionals. What Congo did was it was an excellent moving light desk for busking, but it also was designed to handle theatrical-style events. It bridged the gap between rock concerts and conventional theatre performances.
Even just in the UI, Congo looked like it belonged in the 21st century. It ran on Windows XP, you could move the docks and tabs around -- you could customize every part of your experience working with Congo. With Express(ion)-style desks and their mostly black and white interfaces, everything looked dated (because it was).
If you went to ETC in 2005 and asked for a theatrical lighting console that programmed moving lights really well, your choices were Express(ion), Obsession II, or Congo. Congo was announced in 2004 and remember that Eos didn't show up until 2006, so there was a two-year gap where the only truly appropriate moving light console from ETC was Congo. Even when Eos came out in 2006, it came out at the same time as the Congo Jr.
While Eos was really only affordable by a small(er) slice of the market, a Congo Jr. was at a much more reasonable price point for a modern lighting console. If you were an American shopping for a lighting console, you could pay a lot more money and get an Eos, which is exactly what you'd imagine a modern lighting console to look and feel like if you grew up on Express(ion) consoles, but you'd have to pay a lot more for it than the cost of a Congo Jr., which has that funky syntax you'd have to learn.
Then by 2007 when Ion was announced, the American market really got the console that they had been waiting for ETC to make. Europe was happy with Congo/Congo Jr., and and America finally got their next generation of Express(ion) consoles. With no price difference between an Ion and a Congo Jr, it was a logical choice that many places picked up Ions because Ions were a lot like every other lighting console they had touched in the previous decade, but with the fresh new UI on the Embedded Windows XP platform. And so Congo fell by the wayside in the American markets.
For that 2-3 year gap between the release of Congo and the release of Ion, Congo was the console that made the most sense to a lot of venues, and once Eos came out, those venues that really wanted Eos would have to justify spending a significantly greater amount of money on one of those than if they picked up a Congo Jr., which was as powerful as a full-size Congo in a smaller foot-print -- by all means you were getting a deal on a Jr. in comparison to the price tag of an Eos.
Meanwhile in Europe, nobody gave a second thought to how Congo behaved -- they were used to that style of lighting console already. Congo didn't seem like a brand new console as much as it seemed like a new interation of an earlier console they had already come to love. My understanding is that even today, Congo-series consoles sell in Europe like Eos-series consoles do in the United States (although it's also my understanding that Eos has had some pretty good global success).
Congo was never really a console for the American market. You could say that the American market wasn't ready for it, but truthfully I don't think they were ever going to be ready for it -- Americans wanted a new Express-style desk that looked like it belonged in the 21st century (that is except for all of those people who would've been perfectly happy if ETC kept making Express consoles to this day, and for those of you that were around when ETC announced the end of the Express line, you know what I'm talking about when I say some users came along kicking and screaming through that dark period of theatrical lighting history).
Like how NRA members protest about about how the government should keep its filthy hands off of their guns, Express users would talk about big of a mistake ETC was making by dropping Express. (I'd say ETC's done pretty well for themselves with that decision, wouldn't you?)
Before Eos/Ion/Congo, there were the Obsession II and Express(ion) consoles in ETC's product line. At their time, those consoles were "adequate" at programming automated fixtures. Then ETC developed Congo with Avab. Congo was based on Avab's Pronto console, and Avab had a large enough presence in Europen that when Congo came out, European programmers felt very comfortable in front of them. Us Americans balked at the syntax and a lot of people never got past that, but for the European market there was nothing unnatural about it.
In North America, everyone was loving their Express(ion)/Obsession consoles. Idea/Acclaim/Vision -- all of ETC's earlier consoles looked much like the Express(ion) consoles, so by the time Express rolled around, lots of people in the United States were already hooked on that style of console. Even with the Strand's older (and newer consoles), they were a lot like Express in that any way you spoke to the console, the console would do what you expected it to. You could speak (and type in) the commands in a half-dozen different ways, but so long as your sentence made grammatical sense, there was a good chance you'd get what you want.
Congo was ETC's major diversion from Express-style consoles. Congo was fundamentally more different from Express/Obsession than Express from the consoles Fred was building with his brother out of their parents' garage. It was unlike any console ETC had ever worked on.
It was ETC's jump big jump into controlling moving lights. Congo was leagues ahead at that time from anything else ETC and their competitors offered. If you wanted a Hog, you could go that route, but most Hog programmers will tell you they aren't great consoles for handling conventionals. What Congo did was it was an excellent moving light desk for busking, but it also was designed to handle theatrical-style events. It bridged the gap between rock concerts and conventional theatre performances.
Even just in the UI, Congo looked like it belonged in the 21st century. It ran on Windows XP, you could move the docks and tabs around -- you could customize every part of your experience working with Congo. With Express(ion)-style desks and their mostly black and white interfaces, everything looked dated (because it was).
If you went to ETC in 2005 and asked for a theatrical lighting console that programmed moving lights really well, your choices were Express(ion), Obsession II, or Congo. Congo was announced in 2004 and remember that Eos didn't show up until 2006, so there was a two-year gap where the only truly appropriate moving light console from ETC was Congo. Even when Eos came out in 2006, it came out at the same time as the Congo Jr.
While Eos was really only affordable by a small(er) slice of the market, a Congo Jr. was at a much more reasonable price point for a modern lighting console. If you were an American shopping for a lighting console, you could pay a lot more money and get an Eos, which is exactly what you'd imagine a modern lighting console to look and feel like if you grew up on Express(ion) consoles, but you'd have to pay a lot more for it than the cost of a Congo Jr., which has that funky syntax you'd have to learn.
Then by 2007 when Ion was announced, the American market really got the console that they had been waiting for ETC to make. Europe was happy with Congo/Congo Jr., and and America finally got their next generation of Express(ion) consoles. With no price difference between an Ion and a Congo Jr, it was a logical choice that many places picked up Ions because Ions were a lot like every other lighting console they had touched in the previous decade, but with the fresh new UI on the Embedded Windows XP platform. And so Congo fell by the wayside in the American markets.
For that 2-3 year gap between the release of Congo and the release of Ion, Congo was the console that made the most sense to a lot of venues, and once Eos came out, those venues that really wanted Eos would have to justify spending a significantly greater amount of money on one of those than if they picked up a Congo Jr., which was as powerful as a full-size Congo in a smaller foot-print -- by all means you were getting a deal on a Jr. in comparison to the price tag of an Eos.
Meanwhile in Europe, nobody gave a second thought to how Congo behaved -- they were used to that style of lighting console already. Congo didn't seem like a brand new console as much as it seemed like a new interation of an earlier console they had already come to love. My understanding is that even today, Congo-series consoles sell in Europe like Eos-series consoles do in the United States (although it's also my understanding that Eos has had some pretty good global success).
Congo was never really a console for the American market. You could say that the American market wasn't ready for it, but truthfully I don't think they were ever going to be ready for it -- Americans wanted a new Express-style desk that looked like it belonged in the 21st century (that is except for all of those people who would've been perfectly happy if ETC kept making Express consoles to this day, and for those of you that were around when ETC announced the end of the Express line, you know what I'm talking about when I say some users came along kicking and screaming through that dark period of theatrical lighting history).
Like how NRA members protest about about how the government should keep its filthy hands off of their guns, Express users would talk about big of a mistake ETC was making by dropping Express. (I'd say ETC's done pretty well for themselves with that decision, wouldn't you?)