i have the TS-E 24mm 3.5 (version 1)on the (5dm2) and it is hands down the sharpest lens i have ever used.
as far as i can tell, the difference between the old version and the new version is the fact that you can rotate the tilt to shift without removing the 4 set screws on the lens. otherwise, i think the glass is exactly the same.
when i got my lens, the tilt and the shift were aligned with each other. i pulled the screws out and set the tilt to shift back to the factory alignment.
i am doing the conversion again back to the other way right now actually.
would anyone like to see photos of the conversion?
if so, should i start a new thread showing the details of the operation?
You wish, I've had both and the Mk2 is considerably sharper!
But the really big difference is the lack of CA on the Mk2.