Did Alamo from the airport last trip, but with the fees it got a bit pricey. The minivan had a clunking in the rear, so they upgraded us to a 12 pass van free of charge. Good experience overall.
Europcar actually got good reviews from another couple, and they are right at the airport too.
Good Luck! Enjoy your trip! JUST REMEMBER to have PESOs for Gas. They do not take CC or American $!
We were in the Yucatan this past December. Got an Avis car at the Cancun airport and headed straight to Uxmal via the tollroad and Merida. Needed to get gas on the way back, and in a little town that I can't remember the name of right now, they wouldn't take USD, and we didn't have enough Pesos, so we whipped out AmEx (my preferred) and they wouldn't take that, but they saw VISA and we were in business. Back on the main road, coming down from Cancun to PDC (again via the tollroad from Merida, where at one of the midway gas stations, we exchanged American bills for American coin - almost got a great exchange rate, they wanted to give us eight quarters for each USD!), we stopped at a 7-11, and they took any card you had (including AmEx).
One thing to remember about Mexico and AmEx, a vendor, even with an AmEx sticker on the door, will often tell you that your AmEx card has been refused. This is due to the fact that AmEx charges a higher fee than VISA/MC, but if you ask them to run it again, and tell them that is the only way you can pay, for some reason, that second time, your card will be golden.
Have a spare 200 Peso bill hidden in your "secret" pocket, just in case you get in a jam (but remember that gas down there is sold by the litre, and pretty durned expensive). 200 Pesos might only get you enough to get to the next Pemex station.
:cool2: