Downtown today, at PSU, I saw one of the GMC Denali bikes...well, part of it...it had been converted to a single speed or fixed gear. The welds looked intact...no blobs or holes, but they had some of the deepest ripples I'd ever seen in welds on a bike frame. Headset and crankset looked to be very low quality. Couldn't tell much in observing the wheels. Bike had a lot of road dirt on it.
Interesting about the bikeforums review I posted the link to in the earlier comment; The OP suggested he was a very strong rider, and got 6000 miles out of the bike before a collision with a tree or a pole after a run in with a motor vehicle. His review of the Denali, high opinion of it, and claims about his performance on the bike were received very controversially by readers at bikeforums. The thread went to 50 some pages.