I just dont see it working. I/D causing diarrhea, cats coming in blocked on their c/d diet. The only diet they make that I've seen work is the z/d, but it has high fat, so not good for IBD, only skin issues.

I just have not seen a track record with it that I like.

Royal Canin has it together on that front, and Purina is really growing into it's own.

It is promoted because Vets get told to use it.

I love royal canin SO/calm. My boy blocked at 2 yrs old and likes to make Crystal's, when I switched to c/d for a month because of back order issues, he reblocked. Never again. He is now almost 9 and urine is crystal free. Now I order bags in advance so that never happens.