Judging by other reviews this game should have been a disappointment. But it is not. Of course, a lot of it is a fair criticism. The game does have some issues: performance is bad, moment to moment gameplay and shooter / melee mechanics feel quite clunky.
But the story is good. Some of the side content is fantastic, and the endings? They have actually nailed them. A rare huge story focused game ends as well as this one. It is quite short if you only go the main story path, but let's be real: if you buy a game like that, you should expect side content to be as much of a main dish as the main story path, right?
Do keep in mind that you need a monster of a pc to run this at decent graphics settings, and even then expect to encounter occasional glitch or crash.
Gameplay is nothing to write home about. It gets the job done, it's somewhat competent but don't expect any revelations or surprises there: what you see is what you get. Melee is especially unsatisfying, because c'mon. It's a first person game, of course it won't be satisfying. The rest is just clunky. Not the end of the world, but if the only thing you care about is moment to moment gameplay, you might be disappointed.
All in all? Could have been better, but it is absolutely worth your time if you like a good story and some open world content and don't mind a glitch or two.