Best Move?

I was way up in material and ended up with the W, but I missed the bishop capture here. Seems like that would be the best move, but the engine is telling me the rook move (the one I made) was actually best. Just wondering if someone can explain why. Thanks!

Also, gg to Garneria! I was up material the entire game and he fought until the bitter end. Respect!

Hmm. When I ran Game Review, it said taking the bishop and promoting was better.

This is one of those cases that doesn't really matter which move is the "best". You're completely winning and whether one move has a perfect mate in 6 vs. another with mate in 8 doesn't change that. As long as you don't both hang your rook and allow him to stop your pawn, you'd be fine either way.