I use Thrifty in exactly one place: Providence. At that location, Hertz tries all sorts of tricks, like pretending that your Gold res isn't really Gold, plus they're ridiculously expensive.

National is my #2 choice, but only when they have Emerald Aisle, which they don't at PVD. National's franchisee at PVD is awful, and I won't use them.

So there, I use Thrifty. Reasonable cars, reasonble prices, good service. The agent is in terminal, and the shuttle is frequent because they run a parking lot service. If I have a lot of bags, it's actually more convenient than the garage where Hertz is.

I have a Blue Chip card now, but haven't used it yet as I've ended up flying through Hartford a lot instead of Providence.