Other Car Rental Programs (ie. Alamo, Enterprise) - Payless at SFO - good or bad?

Anybody use Payless in SFO? I read this blog article (http://www.hoteldealsrevealed.com/blog/payless-car-rental-sfo/) and have other reviews about them being quite horrible... but they're so darn cheap. :-(

Take BART to San Burno/Millbrae and find good and cheaper car rental at San Burno/Millbrae Area. they will pick you up from BART station

They're a few miles off airport, not in the consolidated rental facility like all of the other agencies. They are also the subject of many complaints. Rent at your own risk...