I'm looking for a mostly black mouse (the trackball itself has to be black) that's okay for 50 bucks or less.
Color choice? HAHAHAHA, you're funny.
It's a small market, made worse by the fact that they don't get abused like mice and can be built stronger and therefore they tend to last a long time (I replace my desktop mouse pretty much every year). Trackballs are great for Photoshop, cad, 3d rendering, movie editing, etc... You get a lot of precise control.
There are a couple different types, which should be your primary focus, not color choice. Do you want this to look cool on your desk or do you actually want to use it? Some are right of left handed, some work off your fingers, some operate with your thumb, some are ergo, some are not. In my experience, the Logitech Marble ones tend to function he best, though the Kensington ones work very well too, but the one I had was HUGE.
A few customers of mine have ergo thumb models which work fantastic for them. For me, after decades of riding bicycles, it aggravates my arthritis. If thumb shifters on a mountain bike, or thumb throttle on an ATV bothers you, you do not want that style trackball. If you have carpal tunnel in your wrist though, these are a godsend.
My mom on the other hand has a Trackman Marble which is an ambidextrious finger model, I think we've had to clean it twice. Hers is around ten years old, and was used when she got it. These too are great for carpal tunnel sufferers. She LOVES hers, when it breaks, we will have to find another. She can only use a mouse for maybe an hour, this she can use all day. I can use it comfortably, but it slows me down a bit, I simply can't move it fast enough (especially for gaming), though that may just be a mater of tuning but since I don't use it...
Before that was the boxy Kensington I bought to try, it had a (nearly) 3in ball, that one we both could use, it was FANTASTIC for Photoshop and cad, it gave you a ton of control. She used it after I gave up on it and it was the first device she could use all day without pain, it just wasn't very comfortable. She used this for a while before she found the Trackman Marble (I think she found it used for $5 at an estate sale). The Kensington works great for kids, big buttons and ball, I think a gorilla could use it (and probably not break it!).
In the end, she prefers the Logitech for her wrist, I prefer super high res mice.
