I must admit that I was a sceptic when I initially got 3D for my PC and when i first started playing in 3D I was like "there is nothing so great in this". But now after using it for close to 2 years, I just cannot play games in "2D". When you first start using 3D it takes allot of getting used to. I used to get headaches after a few minutes of playing, the depth would play tricks on my mind, I used to get tired quickly etc etc. After about a month I got used to it and since then I always play in 3D unless the game doesn't support it. For me personally I don't play games for hours together like many others here, I just play for a maximum of 1-2 hours and call it quits. If you are one of those who plays for extended periods then I would recommend you stay away from 3D. Playing for soo long in 3D will have its consequences.
Playing in 3D is allot of fun and some games you need to see to believe. It adds an extra dimension to the game and you actually feel more involved in the game, it becomes more fun. 3D is something you need to get used to and after that you wont go back to the normal thing. My use of 3D ends with games, I hate movies and TV in 3D where it doesn't actually do much but for games its a whole other story. If any of you get a chance please check out Trine 2 in 3D (3D Vision 2), it will be the best thing you will ever see, till date, on 3D. After that you will stop calling 3D a gimmick