GL ES1 vs ES2 (for iOS)

From what I understand, on a purely technical level, ES2 is supposed to be faster than ES1- but I’ve read on the unity forums that if you’re developing for iOS you should stick with ES1. Is that really the case? If so what’s the reasoning behind it?

The minimum target spec for my game is the iPhone4, so I was hoping I could use something a little more interesting than fixed function shaders- but if it’s going to impact performance that’s a different story.

I’d love to hear some expert opinions on this, my knowledge on shader performance is minimal.

Thanks in advance!

I’ve mentioned several places on the forum that the only reason people have said 1.1 is slower, is that the built-in “mobile” shaders aren’t written in GLSL. Changing that fixes everything; the emulation is dog slow, making them unsuitable for their intended use.

P.S. The iPhone 4 and iPad 1 are garbage for GPU performance; please support the 3GS as a minimum instead. It runs better unless you are CPU-bound.