I also have the MOD CQD MARK II. Its a great knife. I've had problems with it twice, both were due to blade play. The second time I contacted MOD about it Mike Janich himself took care of me and basically sent me a brand new knife saying that he has never seen my odd problem before. (Used my old blade and put it into new handles etc.) All in all Im happy with it, and their customer service is even better.
As far as the knife, the blade will get skuffed up if you cut rough things, but what knife doesnt? The handles are alum, so if you drop them on rocks etc, it will get skuffed as well. Either way, the knife is well built and should take anything you can throw at it. Just make sure to NOT I repeat NOT wirst flick the blade as the plunge lock is not meant for that type of abuse.