[Perfectlap]

AIO is a polish. It cleans the paint and adds some protection.
AIO is formulated to stick to SG. So I guess you should use one
immediately after the other.
SG is merely a sealant that needs 8 hours to cure.
If you want that wet look layer many coats of SG.

P21S and other Carnauabas are overkill in my opininon. And on certain
colors the shine is nicer by just leaving SG alone.
Silver works well with Carnauba.
By the way S100 is 1/3 the cost of P21S and is essentialy the same.