Yes I know this airport needs some serious updating. From the nasty smell in it, the suspect carpeting and the lack of eating and shopping options, one may think that this airport deserves a 1 star rating especially in this age. Except for Terminal D (I think), this airport looks like it was built when my grandmother was born and never upgraded.
But...having said that...McCarran is the only airport where I've had my smoothest flying experiences. Easy parking and passenger pick ups, close access to the free-ways, plenty of cabs and that shuttle to the Rent A Car Center are some of the few things that make this airport convenient.
Seamless check in situations, a fast security line, easy access to gates are all things that make flying a little more pleasant and much less cumbersome. Luggage gets to the carousels fast and efficiently. Also, flights in and out of Vegas seem to have much fewer delays than any other airport I've encountered.
Since my priority in being at an airport involves getting to my destination on time/ASAP or getting back home if I'm coming back to Vegas as soon as possible...McCarran seems to be taking care of me.