The Kriss is a hoot for sure. EXTREMELY fast. Handles very well. Recoil is low and the thing is very manageable in sustained fire, although I do have a tendency to pull it to the right, at least so far. Maybe I'll improve if I shoot it more, but my ability to shoot the thing isn't going to be a departmental priority.
Re: maintenance...yeah, it's an issue. Mainly lack of lube and RDS maintaining a consistent zero. These things get carried around and racked a lot, generally banged up, but not necessarily shot all that much, and when they are then everyone cleans 'em up before going home. Theoretically.