The security line at McCarran is brutal. At peak times, I've never seen anything longer. Semi-drunk frat guys, sweaty obese people in tank tops, old people carrying their oxygen tanks and of course brats in strollers... you get it all in Vegas where all walks of humanity have to go home eventually. I can't blame the TSA screeners. They try to get people through the lines as quickly as possible, but they're woefully understaffed. I even witnessed a screener get into a shouting match with some moron once who didn't know or want to know how to place his belongings in a bin.
Once you get through security, McCarran is not bad but it sure is big. You'll have to hop on a tram to get to half of the gates. Not a big deal, but just give yourself time. The airport has all the cinnabon and hudson news you could need with plenty of bars, restaurants and of course slot machines. Almost as fun as flying out of McCarran is flying in on a Friday or Saturday evening. Amateur hour indeed. However, I must say McCarran has a bitchin' setup for rental cars with a major rental car complex. Very efficient and user friendly. Maybe there's a review coming for that.