USAA uses TrueCar to power its results...so do many other sites--and all the prices from all the sites are the same when using TrueCar as the underlying pricing engine.

What you get is a price below the meaningless invoice price, but still more than you would pay if you negotiated on your own. If you are not a USAA member, I would TrueCar a dealer at least 100 miles from you as you have to input your contact data. That's how TrueCar gets its money--when you buy a car they get a kickback. You then want to go to a dealer whom you didn't get TrueCar pricing from and you'll then be able to negotiate without him having to factor in the payment he has to send to them. You'll get a better price and know a target to be under.

If you're a USAA member it can make sense to TrueCar it. There are a couple of benefits. You can get a lower auto loan interest rate if you buy through their auto buying service. USAA also has some really good rebates on some vehicles that are beyond and in addition to what the manufacturer is offering. Last, even when using the USAA/TrueCar auto buying service, you don't have to take the price offered. Go back and forth with the dealer on-line and he'll drop the price more over a couple of days.