I use the little puck one and really like it. I’d reckon about 50% of the designers at our studio use one t00.
First, it makes CAD a little more enjoyable. it takes a week to get used to it, but then it’s really easy
As Slippyfish points out, it’s way more ergonomic - if you’ve ever had CTRL button pinky finger, you know what I’m talking about
SpaceMouse used to send out demo units on loan, so you could try it out. Maybe they still do?