MannaPro is a well known brand and a good complete diet for rabbits. It's very commonly used among show and meat breeders. If your rabbit is neutered though, it might be a bit high in energy/protein, but for growing or breeding rabbits it's a very balanced feed. It's among my top 3 choices in feed, and I feed exclusively pellets.
There's multiple ways to feed a rabbit. While many pet store brand pellets are only meant to be a supplement, some pellets are formulated to be a complete diet, and MannaPro is one of them. Of course, it's still a good idea to offer hay, especially if your rabbit is prone to stress or GI stasis.