I couldnt stand GTAIV at all. I played two missions in it before I gave up and traded the game back in. Anything where Im forced to take people out in horrid minigames such as bowling and darts just to get access to more missions, it wasnt worth it to me. Online play got pretty boring pretty fast. I actually enjoyed Saints Row way more than GTA. GTA4 didnt really bring anything new to the table aside from some very bad features. They couldnt keep me intrested in it long enough to see any of its finer points, if it has any.
On the other hand, Ive seen MGS4 turn players who hated the original games into huge Metal Gear fans. Some going as far as replaying and enjoying the first ones. The story, no shock there, was down right incredible as it was expected to be for the final instalation in the Solid series. I dont have anything bad to say about MGS4 at all. Thats just my opinion on it.
