Here's my experience, you decide.
Reservation rate not honoured - I booked on Thrifty.com and displayed the printouts of my confirmation and reminder emails. Neither stated I was booking an AMEX rate (which I do not possess). I booked another reso on my phone at the counter ($40 cheaper than the agent was quoting).
Car broke - Several days into the rental, the parking brake and power steering lights came on. The first agent I spoke with was unhelpfully insisting I describe to her the power steering light. After another call and a 7 hour wait, a new car was delivered.
Extra charges - The reservation I made in haste at the counter was for the default 12 noon return. Originally my reso was for a 730pm return which is when I did return it, incurring an extra day charge. Admittedly, this error was mine though no account was made for the 7 hours I was without a car, or the shoddy service I'd received to this point.
Poor Agent Attitude - agents displayed "that's the policy" attitude. One or two bad apples are understandable but the lack of happiness and compassion was consistent and indicative of a sour corporate culture where empowerment is not core to the employees credo.