The only one I have ever tried is Evo RM...........and I mix that in with our feeding regiment at 25%. I do it to be sure they are getting varied meat sources.
I would just like to add that all the grain free foods I have seen (including Evo) use white potatoes instead of rice as a filler, so I don't really see the big difference in using grain free instead of a good 'regular' corn free. It's still starch, just my opinion of course