Stay the bloody hell away from Wings Aloft. You have to pay for your checkouts in the aircraft and then "work" it off. If you leave, then you owe them money. Last I saw, they were having serious cash flow problems and were having their staff put gas on their own credit cards and then being slow about reimbursing them with no regard to the interest rate of the card.
Wings has good people, but no one that I knew really liked it there. PAVCO is good, but I think the new toll bridge is going to effect business. I didn't think they were hurting that bad for CFI's.
If I had to pick, I would go with PAVCO, assuming you can get along with Mike, the owner. Check out the comments on him on airnav.com then make your decision.
CD