I ordered a M570 to try out. Will try to post a review sometime.
I know that trackball, has a good mechanics and optical sensors, but is completely different than the one I mentioned, on the ergonomics side.
I can also forsee a wild Bondo mod if you wanted to get crazy.
This was more or less the idea I had when the first optical logitech trackball was presented in the early 2000s, but I was too lazy to do it.
BTW this is the first time ever that i read the word bondo.
It's always funny to see how some technical equipment is called differently on different countries.
One of the funniest is what in Italy is called "tubetto sterling" (sterling pipe), is called "spagetti insulator" in the US...:smile::redface: