We rented from Dollar in Vegas (not the same but bear with me).
The car was easily the best priced (almost half price for the same motor from Hertz). This however meant the queue at the desk was massive. I really wished I could join the express queue.
I found going through BA and renting from Avis to produce the best overall deals, became an Avis Preferred member for express service. Also get airmiles. Worth checking online, all their prices are inclusive so no extras hiding in the small print.