Yet again, agree totally with Wayne
DH used to be a frequent user of both
Avis/Hertz in Europe (probably about 20 rentals per year with each) and had status with them so used them often, with little to complain about, apart from Hertz last January (long story and not for this thread).
Last month I used Alamo, and was quite happy with them. Which? gives them a higher customer satisfaction score than Avis and Hertz. I had not realised that you can cancel with Alamo penalty-free until up to 7 days before pick up, whereas the others charge a cancellation fee. That's a big tick from me
As far as Tampa airport is concerned, we prefer it to MCO (but because we now use Manchester more often, MCO it has to be for a direct flight!) However, we spend the night in a nearby Tampa hotel (even used the in-Airport Marriott once) and start our holiday the next day. We used Tampa in August this year and in January 2013, and both times experienced the major road works near downtown Tampa on 275. We had left plenty of time so not a problem, but I wouldn't cut it fine on the journey back to the airport.
Flying home from TPA suits us quite well because we check out at 11 am, go off I4 for lunch somewhere and arrive at the airport mid afternoon for our early evening flight back. No hanging around the hotel or marking time. I could never be one of those people spending their last morning in the parks - when I'm leaving, I want to be on my way