I actually just got some Elation Design LED 36s in. I'll have to do a side by side with a a S4
Par with wide and medium lenses as well as 575w and 750w lamps with different
gel. When I get the chance, I'll be sure to post the results.
LEDs are defiantly getting better, but as stated, they still aren't a Mack Truck yet. The other problem with LEDs is they are color additive, not subtractive. Now while some view this as a bonus, I don't because certain colors stuffer that way. For instance, blue LEDs put out a much lower lux then red and green LEDs. A dark blue on LEDs is still going to be lower in intensity then a S4 with R80 in it, because the S4 starts out high powered, while the LEDs get there strength from adding multiply LED colors together at once. The other problem is as you spread an LED beam with frost or lenses, the intensity drops off very fast. For example, a S4 Parnel going from a narrow spot to a flood at a distance of 30 ft loses 76% of its lux. An Opti Par RGB in the same instance loses 89% of its lux. These numbers are rounded, but you get the idea. You lose more light spreading LEDs then spreading a normal lamp. 13% isn't much, but when you are talking about Parnel going from 2076.68 lux to 516.48 lux and the LED going from 50.2 lux to 5.4 lux, the LEDs aren't looking so good.
LEDs aren't cheap enough yet to solve the problem with throwing numbers at it yet. In the example above, you need 10x the LEDs to get the same white output as a regular light. With the LED costing $600 a piece and the Parnel costing $215 with lamp, the S4s are still winning. Don't get me wrong, I love the ability to color mix and strobe, as well as not have to play with lamps and gels anymore. They just need to make them cheaper and more powerful before they become more mainstream.