Overrated: GTA V-Online. TOO many reasons, it is a hell of a success, yet too many complaints, lunatic players which think this game is the MASTERPIECE of this century, (from simple to complex) problems than the majority of players dosen't care, either by being ignorants, or by being the random kids which we know are the main reason to these problems continues...
Dosen't matter if is a record or a problem which appears, people treat GTA V-Online diferent than the others GTA's, i would say about SA, VC or even III but .... congrats people .... you made the V-Online looks worst and more annoying (in some aspects) than the all former overrated GTA's together.
Underrrated: GTA Chinatown Wars. Man this is a simple game made for simple consoles, yet they are fun and a bit interesting, those diferent minigames ranging from car stealing, opening a truck with guns, opening a car with a hidden stash of drugs etc... they were nice and looked unique for the standard GTA (they looked more amazing and insane if we consider how they worked with the touch screen system of the DS).
The other thing that caught my attention is the controversial drug dealing based on supply-demand, people can whine about the hey look, GTA shouldn't be here, this console is for kids and etc ... but for a GTA that was insane and a great way to make money. people complained about the over the top gameplay, but this made the game unique, a bit annoying sometimes but nothing to compromise and affect the gameplay.
To a less extent, one of the former DLC's from GTA IV: The Lost And Dammed. This game-DLC never got that attention like IV and TBOGT, only the specified groups that like the style of game, story etc... liked TLAD, for a GTA game, this game got a non-sense hate (probally because the TBOGT had more interesting vehicles, dancing minigame, etc...), yet the focus and how the Biker theme worked better than whole TBOGT, it was pretty much which made one of the most interestings GTA's for me, the plot, the protag aka Jonhny Klebitz, the range of avaliable bikes from sports to dam choppers, the air hockey and arm wrestilng minigames and even the biker gang war, it was a nice and interesting game.