Trackball vs a Regular Mouse- When and For Whom?

GRS LED Arcade Trackball | TS-UTB-01

I'm irrationally excited for this trackball gaming mouse

Logitech ERGO M575 Wireless Trackball Mouse - Easy thumb control, precision and smooth tracking, ergonomic comfort design, for Windows, PC and Mac with Bluetooth and USB capabilities - Graphite

ELECOM Relacon Handheld Trackball Pointer, Ergonomic Thumb Mouse for Right or Left Hand, Bluetooth, 10 Buttons for TV, Presentation, Game, PC & MAC