There's not much to say about cryo treatment. It works, it's cheap, and if you have issues with burning up rotors, it makes a significant difference. The only time you wouldn't cryo the rotors is if the OEM rotors are so cheap you can replace them three times for the cost of cryo treatment.
Cryo typically triples rotor life, regardless of the designs or patterns cut into the disc. All the Supra guys I know who do track days swear by it. Andi Baritchi, fourth place in his debut One Lap of America in his Supra, swears by it. Even gunsmiths acknowledge there is a benefit to cryogenic metal treatment, and they're the most picky metallurgists you'll ever find.
Not much else to say about it except do it.