I'm PC Platinum ambassador right now. I like accumulating the points for future trips (about 240K), but the benefits of upgrades, concierge rooms, etc. are not that great imho. The PC properties don't often have that much to offer. I will enjoy the airport Crowne Plaza this week in St. Louis and at least there is a place for snacks and drinks there, but this doesn't happen very often.

Hilton has given us much more in terms of upgrades, use of points, etc. So my own experience would certainly lean toward Hilton.