You can't cryo humbuckers, only single coils - I've asked! I bought a set of cryo Fralin p'ups from Callaham last year for my Strat along with cryo-ed electics/pots. I have no idea how much better they are compared to non-cryo p'ups of the same type but I liked them a lot more than my Kinman Woodstocks. They were the same price as non cryo, so I thought why not! It's the same reason why I use GHS sub zero strings.