Overall, McCarran International is not a bad airport. It's kind of like a Disneyland type of funworld for adults. They have a monorail and they have slot machines and free wifi. It is clean and there are no areas that are under construction. They've got those conveyor belt walkways which are all over Vegas hotels which help you walk less.
What is LAME here is that the rent a car area is NOT in the airport itself. You have to be bused to the rent a car building and it takes more than 5 minutes. Really? Sorry, but the rent a car booths should be in the airport. It's kind of a hassle to have to get on a bus with your luggage and you have to spend extra money on the tip you will have to give the guy that takes your luggage and places it on the rack inside the bus.