
I used in Centuaro when arriving at Alicante. Car we got was small, but nice and new. Agree that the "return empty" policy can be a bit of a pain, but otherwise, no problem.
I went with Hertz when we went to Sardinia in October, did it through Top Cashback and got £18 back - every little helps.
Oh and use these guys to cover your excess in case of any prangs - http://insurance4carhire.com