yes. the mkII is the sharpest between the two.
CA is well controlled and AF is lightning fast.
do a search online and you can find more results.
if you can afford it, get it.
i promise you that you would not regret it.
price ranges from 3.1 to 3.3+k.
I have not used the 70-200f2.8 IS Mk 1. But I used to own a 70-200f4IS. used to, because I sold it during my upgrade to 70-200f2.8 IS Mk 2. why? because the Mk 2 is as sharp as the f4IS wide open (f2.8 vs f4), and allows much more light in.
only regret is the weight. not even the money. this lens is worth every cents of what I paid. enough said?
I got no experience with either. But overseas forum like POTN Canon and FM are full of praises for the Mark II's sharpness wide open as if it was a prime lens.