i currently use an ELECOM relacon handheld wireless trackball and, for the most part, it has been great! i bought it around august of last year, so it's nearly a year old.
it has started showing its age, unfortunately, in the form of the scrollwheel not working very well. everything else is still fine, and maybe i can just open it up and clean it or something, but looking it up online i see a lot of people having issues with the scroll wheel and the issue is usually that one of the arms inside broke, so it might just not be as well-constructed as it could be (and to be fair i've dropped it a good few times, so that's probably also a factor). if not for this one issue, i'd have no complaints other than maybe the DPI button is a bit sensitive.
does anyone have a similar bit of hardware they can recommend that plays nicely with linux? i have kind of a unique setup (i sit on a couch several feet away from the TV that my tower is plugged into) and this has been working way better than trying to use a regular mouse on the couch, and honestly just feels better in general than using a mouse now that i'm used to it.