Camshafts

Do all aftermarket camshafts out for the rsx-s work for the 06 si? On clubrsx there all crower cams that say fit any k20 head. Stage 2 says 50+ HP with built type s with ecu for stock type-s. What specifically makes a type-s "built"? Is it just valve springs and retainers or what else? What kind of benefits power wise do you think just stage 1 would make? Stage 1 says 35+ hp with ecu for stock type-s. What about other cams that are made for the type-s such as Toda. Are crower the only ones that would work with the si since they say any k20 head?