McCarran sits right below (south of) a ghettoish area of east LV ... and east of the Strip, toward its southern end. In fact, its western fence is ON the Strip. I've always rented a car, so I would have no clue how to get into town. I believe there's a city bus.
The pluses: it's a big Southwest and US Air hub with mostly on time flights and it appears to have enough terminals to spread the gates over, as well as the opportunity to see a jumbo from British, Virgin or Japan Air floating over the clear desert skies to land at this depraved destination while you think "Do THAT many people want to come to LV from all over the world ... on a daily basis?"
The minuses: more tacky people than you see at most airports, slot machines inside the airport, the ginormous luggage carousel room with all the show advertisements up above, very loud, sullen service wherever you go, and the friggin' Pepto Bismol colored interior of at least one major terminal which is a throwback to some other decade and is likely to make you more sick than well.