Finally getting back to this...
My wife likes Jimmy Buffett (mainly because her parents do too), so this might be a thing--but not sure what our travel schedule looks like for the end of the year yet.
I haven't stayed at MGM Grand, but we're planning to in June for a couple days. We did stay at Signature at MGM, which is connected to MGM but a totally separate hotel. The Signature is pretty nice (the kind of place where the TV motors up out of a box at the end of the bed,) especially if you get a balcony room. It's also fairly quiet. The down side is it's nearly a half mile off the strip, so if you forget something in your room you're not just popping back in.
MGM Grand is huge--used to be the largest hotel in the world and is now #3. It's also back off the strip a ways, so it's a lot of walking just to get around there. It also tends to be crowded. It has one of the biggest nightclubs in Vegas at Haakasan--not my thing but a lot of the kids seem to like it. Lots of good dining options too. As far as the hotel goes, it ranges from very basic to extraordinary accommodations. The west wing used to be the Marina hotel, built in 1975, and from everything I've heard those rooms are pretty crappy. Beyond that, I think their standard rooms are solidly middle-range for Vegas. But if you want to spend $$$, the terrace suites ($600+/night) and the SkyLofts ($900+/night) look awesome.
MGM Grand has one of the best pool complexes in Vegas--not quite Mandalay Bay with a sand beach, but a lot bigger than most of the other resorts, plus a lazy river. The Signature rooms get access to it, plus their own smaller pool at the Signature.