I meant to respond to this yesterday but I got a call and forgot. We've been using Manna Pro pellets since May 2007 since we got our first bunny, Billy. It's what both Billy's and Ronnie's breeders were using for all of their Netherland Dwarfs. We started out with the Pro formula, which was fine, but after a year switched to the Sho formula because I believe it has better nutritional values.
We recently tried to switch both bunnies to Oxbow BB&T because of all the talk of alfalfa pellets being bad for them, but neither of them took to it. Ronnie would throw fits and toss the Oxbow all over the cage, Billy would leave his pellets until he was really hungry and then eat only some of the Oxbow. They both love Manna Pro and we've never had a problem with it other than it never having a mill date or expiration date. The mill date thing can be kind of annoying because the last bag we bought from the Tractor Supply ended up being just as stale as the stale pellets we were throwing away...but the bunnies still eat it. We had one bag that was really fresh, and it was so nice, but other than that every bag we've gotten I can tell has been sitting around for a while. That's my only complaint.
No urine sludge or G.I. issues in either bunny.
ETA:
I remember some people saying alfalfa pellets cause weight gain but with our Nethies who are very active I cannot keep enough weight on them. We recently weighed Billy in at 2 pounds 4 ounces and Ronnie at 2 pounds 3 ounces. Each eats between 1/8 - 1/4 cup of Manna Pro per day.
