Is a trackball good for playing games?
Solution 1:
I use a trackball for my computer and am an avid gamer. I play many different games (a lot of minecraft, lots of FPS games, lots of RTS games, etc) and feel that I am just as good with the trackball as I used to be with a mouse. I'm also a software engineer, so I use my computer a very large amount of time every day.
Making the switch to a trackball is definitely something you can do and still successfully game. Not everyone likes trackballs, though, so you may regret your purchase. One thing I would stress is that you should try to force yourself to adjust to the trackball if you want to learn to use it. Unplug your mouse and put it away. Make it so your only option is to learn how to use your trackball or don't use your computer. You WILL have to spend some time adjusting, and during that time you WON'T be as good at games as you had been. Don't fret - just keep trying. I'd say I was back to the same skill level within about 2 weeks, but it may be longer or shorter, depending on how well you adjust.
As far as recommendations, I've only ever used one model, the Logitech Trackman Wheel. You may have better luck going into a B&M store and trying out different models and find one that suits your hand shape.
Either way, I'd highly recommend attempting to switch if you're considering it. I haven't regretted my decision in the slightest.
Solution 2:
When my primary computer was a desktop, I was using a trackball instead of a standard mouse. I had been using a trackball at work, and I was comfortable enough with it there that gaming at home was not a problem either.
There was one exception. When Diablo II came out, my wrist began to bother me from using the trackball 8 hours a day at work and then hours on end at home too. Before the problems got bad enough to affect work or gaming, I switched the trackball at home to my left hand and taught myself to use it that way. (There may have been a few trackballs designed specifically for lefthanded people at the time, but I think I just took one that was somewhat symmetrical and used it on the left side, mapping the buttons appropriately.) That balanced the load enough to stop the soreness in my wrist, and it also gave me options for situations where, for whatever reason, I couldn't put the trackball on my right.
If you are new to trackballs, and you'll be using one for both work and gaming, then you'll probably want to ease into it gradually. You will be using different muscles, and you don't want to put too much of a strain on them at first. (You should also consider tips like these, especially when you're getting used to the trackball.)