The gun customisation is awesome, it's one thing that they got right but still have to unlock attachments in boring challenges.
The game has 8 maps. 8 boring maps, no variance what's so ever, it doesn't even matter if you play against players / bots, It's stale. Sure the objectives are fun but there's no interest in getting back most of the command posts. The MG nests are somewhat useless. The sentry guns are stupid, they work half the time... ( probably just the light version ).
So pretty much Brink is like someone ate single player and multiplayer, felt sick and vomitted on a dvd. Spending 50$ wasn't worth it.