The only issue I've had is losing the sound, I hope that gets fixed soon. Other than that I've had zero problems. I run an http://www.novatech.co.uk/novatech/pc/range/revolution.html and have zero performance problems, I updated the latest drivers before installing Brink.
My biggest gripe would be the [censored] people I play with I'm mostly specced into soldier, but I'm usually forced to change to whatever class the objective need, cos most of the times my teammates arnt capable of doing it in a timely manner (or we dont have said class). Apart from that, few of the objectives are pretty biased towars either team (Reactor first objective as resistance is usually really hard, same goes for hacking the missile as security in that one map). Maybe these could be looked at somehow. I might also look at decreasing time to hack objectives, it's painfully long, although you can move around but its sometimes really hard to get it done. The SMART is awesome when you "think it the right way". If you expect the entire game is endless Mirrors Edge parkour, you are in for a disappointment. It is, however, what it's called: Smooth Movement Across Random Terrain. It's a shooter, not a parkour game, thus a movement system shouldnt control the entire game. Anyways, I love the SMART. Would also love to have some lobby system and the group leader could make the entire group join a server with just one button.
I'm really enjoying Gerund/CARB-combo as a medium. I really dislike the SMGs so I'm likely to stay medium. I feel the Rockstedi could use some love. I want to like the Rhett as well, but somehow I end up going for Gerund usually.
I can wholeheartedly recommend this game for anyone into team based multiplayer FPS. It's amazing. Thanks SD/Bethesda.