I haven't tried any of these products yet. Do they pretty much all compare the same? Can p21s and the souveran be used as one steps? Souveran seems too pricey. (the paste version)
PwC is a polish with carnuba - it leaves a small amount of carnuba protection and cleans and polishes your finish. PS21 and Soureran are Carnuba waxes with little or no cleaning ability. PwC would be the closest to a one step product.
I'm with groebuck, I have P21S and it gives a dark/deep look, but has no cleaners. To be honest, I like the looks of PwC better because it's more reflective and gives one hella glow!
I've never tried or seen Souveran so I can't comment.
Souveran and P21S are known as "toppers". These should be your last step type products. PwC is a step that can be used as a base for such liquid waxes and sealants as Poorboy's EX, EX-P, or Adam's Butter Wax.