I have read that a rental company, maybe Enterprise, has been known to issue "speeding tickets" to renters if the tracking system clocked them going over a certain speed. Basically it's just a big ol' surcharge on your credit card.
I've only ever rented from Hertz, and I've been nothing but happy with them. I've gotten a Mazda 6, a Mercury Mountaineer, and a pair of Tauruses (one Duratec, one Vulcan) from them, never mind that I've always ticked the "Compact" selection on the reservation website.
