I will tell you what you need to know in my Mirror's Edge review.
In the early chapters it was fine and challenging at times but okay. Then it got to the point where it was just basically saying if you use a gun your life and experience will be better. This was not only frustrating but annoying as well. This is especially in the last part of the 8th chapter and the 9th chapter
Additionally there are problems with hit detection with combat. And who the heck made those dark runners invincible. They are sporting some kind of supper fabric mentioned in an elevator news thing. Those did at a bit of side stuff which made the game more richer but sadly there weren't enough of these and the speed of the text needs to freaking slow down. But back on subject of combat since I played through using just melee moves (which again I must tell you it isn't worth the misery to get a meager 80 gamerpoints) so I would like to think I got it down pretty well and let me tell you that the system needs refining and more moves. But ultimately the system is simple to use and has a tiny bit of mastery though you can't beat those dark runners you will meet later. You need to run away from them. Also another problem I came across is why does every other character (not the blues or the PKs) have better melee powers than me. I meen some can do back flips which you can't do, trust me I tried. But this could be looked past if you weren't forced into combat serveral times.
But lets get to the platforming. There is hit detection issues like with combat. Sometimes you won't grab on to the ledge even if you should. This should have been the best aspect of the game. Which it kinda is but not as good as it should have been. Plus we should have had more of it on the roofs. Yeah you only go to give one run the rest of the game is about saving your sister. There is time trials for each stage but if they think I am going to go through that again with a time limit forget it. You can do it but I didn't as of this review.
There are time trials other than the chapters for you to do. But this requires and EA account. Which is free. You can play offline which I guess means it won't be in a leaderboard.
There is a story though some would tell you it doesn't matter, I say it does. It isn't a deep story but it has deep moments. Sorta. It has twists and turns but could have been deeper and flushed out the characters more. Though it is okay.
Presentation: The art style was pretty good. Except for the time I came across white trees on the roof. Yeah someone was way to happy with the white. The style at first good later becomes kinda annoying and bland.
Graphics: It isn't Gears graphics but it does have problems with it. There are issues with blandness but some would say it works. It kinda does but it also kinda backfires a bit. Great to see the character in first person. That is a bonus in my books. IE your body isn't invisible and your hands and feet pop up on screen.
Sound: The music is okay and fits the game. Gunfire sounds okay and your character pants while running so this is a very good aspect of the game.
Gameplay: This is where the game falters. It was fun in places and frustrating in others. Combat is needs improvement. And the story could have been better.
Lasting Appeal: Well it doesn't really have that much lasting appeal other than time trials and speed runs. There could be more downloadable down the road but that is to be seen.
Overall: Overall it is a good entry into a new franchise. Hopefully the sequel will be better and for the love of gamedom please no don't shoot anyone achievement in the sequel. That was bad enough getting it in this one. So definitely a rental and a maybe on buying. I own it but I don't really rent so that isn't a big indicator. You could do worst.