I just started playing Alpha Protocol last night.  I am loving it so far.  I am only an hour in or so, but there is nothing I don't like.  I haven't felt this great on a new game since I played Mass Effect and thought it was the best game ever.  To be fair, Alpha Protocol is a lot like Mass Effect, only without all the Sci-Fi bullshit.

Playing these games back to back turned out, for me, to be an interesting open world comparison. 
 
With the bevy of open-world games out there, you sometimes don't know what exactly you're going to get.  Both games turned out to be fun in their own ways, and both had their weak spots too.  Just Case 2 improved vastly on their grapple and parachute systems which is really the draw for this game, they created a new mechanic for travelling in an open world, where nearly any area you can see, you can get to almost immediately.  It makes travelling in small and large spaces quick and easy.  This mechanic was deeply missed going from one open world game to another where traversing the world is a much slower process.  That being said, the shooting and driving and enemy AI aren't as good as they could or should be.   
 
The Saboteur was a nice surprise coming from Just Cause 2.  I was expecting it to not be as good, but it actually was better in a lot of areas.  The first thing that stood out was the level of polish.  The story was much better, I liked the characters and the dialogue, animations were hugely better. The design of the menus and the black and white/colour film noir style of the game also stood out.  But one of the things that impressed me the most about this game was the shooting.  I don't know if I was tainted coming off of the terrible shooting in Just Cause 2, but it felt really good.  I would draw a comparison to Uncharted 2 in the feel of the shooting, with not as good a cover system. The sneaking and disguising mechanics I feel were done well.  Pretty much every mission can be completed with a patient, stealth approach, so if you enjoy playing games that way, it is absolutely an option.  Or you can just go guns blazing.
 
These games have something different to offer, both suffer the inevitable gameplay repetition of most open world games, but both are worth checking out.