Don't know if this helps, but I've read about Orijen when I was searching for stinky kitty poo, and it seems from the few I read that people like it.
Yes, twice, he's clean. The switch was the direct influence of his stinky poop.
The vet told me that she likes to keep cats on a new diet for at least 4 months before giving up, just to make sure that his system is completely used to it.