If you lube and adjust a Wally world bike... it's not that bad really. The grip shifters can go bad, the rear wheel can go bad, the barrel adjusters on the brake levers can give out....crappy China bikes aren't like bike shop bikes...but honestly, the crappy bikes work pretty well. I've seen poor people ride these $75 bikes for a lot of miles.

I'd ride one coast to coast, no problem. But I would fix along the way, I'm sure. Isn't that part of the adventure?