I stay at the MGM almost every trip to Vegas. It is one of the best values on the Strip.
The beds are comfy, the rooms are big enough including spacious bathrooms (how much time do you really spend in your hotel room in Vegas anyway??). There are so many rooms that I tend to get lost coming off of the elevator. Oh well. If you are looking to turn out the light over the entertainment center, the button is inside next to the TV. No need to rip out the entire wall trying to unplug it.
Room service has been good - never a problem calling down and asking for more towels, etc.
Good bars, plenty of gaming tables. Good shops. Cab lines are not ridiculous. Plenty of Starbucks inside. The pool is great - the lazy river is the best in Vegas. The DJ spins good tunes.
There is a nice balance of young people, older people, and families at the MGM.
Just an overall great experience time and again.