Mike, I don't like pressure treated decks. On our lakehouse I used Trex, but I don't like it and I heard there is a recall on it(which sucks because we built the deck platform, set the hot tub, then framed the house and the screened porch around it).
On this "deck" I got an engineer who does our development projects to design a pan slab. We've got 8" block walls with brick veneer for the 4 sides, with W8X10 steel I-beams on 4' centers and 8"x8" angle for lintels. On top of that we put corrogated steel pans. On top of that will go a 4' thick concrete slab and 1&3/8" concrete pavers. This deck should last awhile, not to mention hold several fat chicks.
Jim