ARMA 2

- Patch it. There's been a couple of major updates since the release and while the game still has many bugs, it's far better now than it was.

- Save regularly. Triggers for missions often don't trigger, so being able to restart the level in the hope the trigger does go off saves you the hassle of playing the whole mission again.

- Slow and steady wins the race. You can use the element of surprise to bushwhack your opponents, but generally speaking if you're running around all over the place you're just making yourself an easy target. Linked to this, it's often easier to take an APC/Helicopter close to your intended target then approach on foot rather than barge right in, it just makes you a bit less noticeable.

- Make use of the time increase function. It makes crawling across a field much more bearable.

- Learn the squad (spacebar) and individual (F Keys) commands, because being able to get your team to do what you want quickly is crucial. I find the team AI ok, but sometimes they do wander around aimlessly in the face of fire and as a team member death is game over, I'd rather they stay alive...

- More than anything though, enjoy it when it works. It's not yet a perfect game because of all the bugs, but if you get a feel for the game it's better than anything else out there at the moment.