Are water suppressors needed in the bathroom sink faucet and the shower stub out also? And can you just use a length of pipe on a T, or must you use those copper chambers? (cpvc system) thanks

I think you're asking about air chambers,( shock absorbers).
"can you just use a lenght of pipe on a T"
You sure can. A piece of CPVC 12" long coming off a tee with a permanent hard cap will make you a dandy air chamber. Regards, Tom