I like Brink a lot. Despite being lucky enough to get both the video bug and the sound bug (not every game though, just pops up on occasion), its still a lot of fun. I got the PC version. A very different game which is well balanced and has the right type of focus. The entire game is about helping your team win rather than improving personal stats.
The SMART system works very well, and is used mainly for getting from point A to point B and then to relocate to a better firing position at point C. While not used in combat much, except for entry or retreat, it changes the game a lot, allowing for rapid redeployment and movement in a very fluid manner.
A big thing in Brink really is moving more than you shoot. If you stay in one place too long, unless it is a choke point defended by others on your team, you WILL get flanked.
The guns feel like they have some weight and they actually have recoil for sustained fire
The assault rifles have very high accuracy for the first couple of shots which deteriorates very quickly. Smgs arent quite as accurate for the first couple shots but they have a much smaller spread, and are effective for sustained fire.
The rifles (their equivelant of snipers) are slow firing but take 2-3 shots to kill (1 for a headshot except on heavys). Only good for a couple levels/ areas on levels but can be used effectively. The play style doesn't support them generally so they are rarely found en masse, max 1-2 players per level. Shotguns are only good for VERY close range, approximately 3m to get an instant kill and it deteriorates very quickly. Outside of like 9m they are essentially useless.
I dont use heavy weapons so I cant comment on them.
The classes are done really well, there is always a pretty even spread of classes, although slightly fewer operatives generally (I might just be a little biased against them because I dont use the class very often). All of the classes are needed to win and there is no class that is "better" than the rest. The upgrades all assist the player rather than make the player, and there are very few must-have upgrades, Its a hard choice picking the upgrades because they are mainly suited to enhance your particular play style.
Guns and gun add-ons are unlocked through a series of challenges rather than earned by leveling up. A nice touch that helps avoid too much swearing at the PC because the opposing player has played more than you and has newer guns. I would advise doing these quickly thought to help you learn the game and to get them done before you advance too many levels, the ai gets much better very rapidly after you start leveling up, normal is actually a challenge after 10 levels or so, and most of the challenges put the ai on defense where they excel (they arent quite so good on attack though).
There are 10 maps that come with the game and while they are varied, they all feel kind of similar. My biggest worry for the game is that they will get stale and that there wont be any/too many new maps.
Overall Id give the game an 8.5. I enjoy playing it a lot, its a very unique experience that is presented beautifully. I doesnt feel like a console port, even though its multi-platform. It plays well despite the bugs, however when playing online the game is sometimes laggy due to either the servers or the netcode, I'm not sure which. If you have the money, its worth getting, but I would wait for some of the bugs to get ironed out before purchasing.