> Some people find it to be more precise as well, but I don't know if there's any evidence apart from personal preference.

Well, for me it is much more precise. Or at least seems more natural.

But... ergonomic warning... I switch up between three different trackballs to keep “trackball thumb” from setting in. I get pain in the base joint if I don’t vary the angle, and also spend some time using a finger-positioned trackball.