I travel for work. Alamo/National has:
Best price
They will use my debit card (I don't use credit at all)
Easy check-in
Great staff
The correct class of car I reserved - no hassles or up-sell
Pick any one you want from the row
Easy return
Accurate bill
I use them almost exclusively. Absolutely no Avis or Enterprise. They have stranded me too many times. Alamo/National is always there to bail me out. Now I tell the Admin that books this stuff to use them exclusively.