Yes - the pictures are only examples of what the text would look like.
I'm not sure what the size limit is, but I'm sure it's within reason. The best thing to do is to
call the manufacturer and tell them what
instrument you're using, what beam spread it is, and what your
throw distance is. They can advise from that
point forward in regard to physical limits, legibility,
etc. Many gobos with more complicated text (especially if multicolor/graphics are needed, or if there is more to it than a simple word or phrase) will need to be made of glass, which is expensive. Basically the answer is - "it depends". In general though, you can't put much more than a phrase on a steel
gobo, and you'll want to use the best
ellipsoidal available.
With a little more info, we can give you a more complete answer. Right now, I can't tell if you're just wanting to say something simple like
"Intermission" or more complex, such as
"Welcome back my friends, to the show that never ends. We're so glad you could attend; come inside, come inside."
Manufacturers generally accept custom gobos via submitted artwork, similar to clipart, so you can have a
gobo that is entirely custom. Keep in mind that some changes will need to be made with steel gobos so that they will hold together (ex: things like O's will need to be bridged since there is nothing to hold the center "dot" together).
If you are going to order a pre-existing design with your own lettering, I'd just
call them.
