Typical McDonald's, located in the food court at the MGM Grand.
Prices are reasonable and no higher than any free standing location and they are open 24 hours.
Cashiers are reasonably friendly, considering what they have to deal with most times (crazy, out of control drunk people). They offer an employee discount the MGM employees - it's not a lot, but it's better than nothing.
The only thing of note is that breakfast is not available 24 hours (like most McDonald's locations) - but starts at 4am.
It always seems like the food is ready quicker than anywhere else I've been. Not sure if that is good or bad!
Basically, if you are too cheap to dine at the other late night option (Wolfgang Puck's), this is a good choice. Especially if you are just getting back from the club.