Not bad but not good either. Almost like Pokemon Stadium except less rental Pokemon and features..you need DP to enjoy.
Well, first of all, the only thing you do in PBR is battle. No mini games, no big screen playback of Diamond or Pearl.. just battling. And customizing your trainer and battle cards are like the only thing not involving you battle.. which is sad really. And worst of all, you DO need Pokemon Diamond and Pearl to actually have fun with this game.
Unlike Stadium's choices of Rental Pokemon, which were like almost the whole list of Pokemon except for major legendaries (like Lugia, Mewtwo, Ho-oh, didn't mention Mew or Celebi because on Stadium 1 and 2 you can unlock them), and were quite decent, Battle Revolution doesn't give you a choice of rentals at all, the rental cards aren't that good.. you do later on get to trade rentals with in game trainers after you beat what they've used.. but they still aren't good. You wouldn't want to go on Wi-Fi with a Card with Rental Pokemon either.
Well, the only good points this had was actually making your own trainer besides looking like the same generic male/female trainer as everyone else, getting the Promotional event Pikachu, Electivire, and Magmortar on your D/P game (If you have it), and battling with your Pokemon in 3D (hence that you have D/P and a DS), other than that, PBR isn't that worth it.