Just received the 12-35 and I'm quite impressed with the performance. It was actually less expensive buying it from DigitalRev than dealers in the USA.
A couple of sample shots taken today at the farmers market:
Pink pond lily
There was some heavy purple fringing along the beams adjacent to the bald sky in this market shot, but easily removed in LR.
and one trial shot with a Hoya R72 filter for IR. Handheld 1/4 sec f/2.8 ISO 400: