My guitar has a push/push knob which feels different than the volume knob. The latter is looser. It's not a HUGE difference but a noticable one, nevertheless. It could also just be because I use the volume knob so much more often than the tone knob. But yeah, the spring crossed my mind as well.
Push/push has my preference by far. I can split the pickup so much faster which is so much more practical and comfortable. I've heard some people claim they are inferior to push/pulls. Because supposedly they switch on by themselves, so to speak, after a while. But I've never really experienced that in the ten years I've had mine.
Yeah CTS is very good. I'm actually having those put on my new custom guitar that Jaden is going to build for me.
There's a lot to pots. I've read the specs of RS Guitarworks' superpots. And there's a truckload of things you can adjust/change/choose. Brass or aluminum shafts, "silk-screening" vs. a "heavy carbon" resistance path etc. It's interesting stuff. But I don't really understand much of these technical things. lol