i was planning to rent from them this summer so i did alot of research, this is what i came out with.
they are the cheapest (not by much tho, only about $50 cheaper per week than budget or others)
but you run the risk of additional charges unscrupulously being tacked on or being conned into insurance that you dont want (if they say sign here, make sure to check which boxes are marked off and what you are signing/initialing)
based on the reviews ive read, certain locations are pretty bad (hidden/false charges, rude employees, reserved car not available, no one to speak to) but others are ok. they usually have decent late model cars. so basically, do your research on your location and im sure a ddf'er can navigate fox car rental