Elecom EX-G Pro vs Logitech M570

For those who care about the "spin factor" of a trackball -- how long the ball will freely spin if you give it a good flick -- I will note that my unit has some spin, but not as much as a broken-in m570. Ergonomics are substantially different than the previous Elecom thumb balls. This model adopts a wider, flatter, slightly longer shape that allows my hand to rest in a somewhat more neutral position compared to the curled-palm grip of the Elecom M-XT3. Compared to the M-XT3, my pinky now rests on the right edge of the mouse instead of on my desk, and my wrist and heel of my hand are elevated slightly off the desk by the extended palm rest

Bottom line, however, is that I NEED this shape in a trackball, and nothing else out there comes close to being what I need. I buy several at a time, fearing that these, too, will be discontinued one day and leave me having to learn how to use a different kind of pointing device that won't be as functional for me even after I get used to it. If you like this design, this trackball is the best option out there, imo, and just do your best not to drop it (unless you need exercise: getting up a lot to track down the ball is not what I think they meant when naming it a "trackball," but is a common need for me!).

Maybe I just got lucky, but I suggest others do the same: wait to test the mouse yourself before ordering any possibly unnecessary additions for it. My main gripe with the mouse, and the reason I'm deducting a star, is for a problem I had not at all anticipated and saw no one else complaining about: the width of the mouse overall and the narrowness of the main left button. Because of the width of the mouse, I have to angle it to the right a little more than I'm used to, to have my thumb comfortably centered on the trackball in a way that allows for the most accuracy; and because of that and the narrowness of the left-click button, I'm always accidentally pressing one of the two buttons that are crammed to the left side of it. This isn't too much of a problem for every day use, such as browsing the web, but can be a bigger issue when playing some games

I would suggest using trackball mouse if you have limited right hand space. logitech M570 is really comfortable for example. But the major issue seems to be that keyboard and how it is too wide, you probably should look for narrower keyboard. Maybe you could find tenkeyless ergo board and use separate numpad on the left?