Yes last january I had a Roadmaster mt. Fury. I paid $53 for it (no joke). Well, it looked nice and shiny there, it rode ok for the first two weeks, then it started to go downhill fast.

For reference, it's a one-piece crank, 21-speed drivetrain, indexed shifting, steel frame, rigid steel fork, stamped caliper brakes, kenda tires, and painted steel rims. Overall it was what I would expect for $53.

The chain started blowing off the chainrings after about two weeks, the front brake bent itself so badly I had to move the rear caliper up front, and eventually the chain snapped (the day I walked into the LBS for a new bike). Given i was a heavy guy, and I liked to stand up and pedal at that time, so I did put lots of torque and strain on that poor bike. Oh, and I also trashed the rear rim to the point of replacement.

That bike lasted just over a month before i put over $60 in repairs. It might have been fine for a 12 year old kid, but it wasnt fine for a 260lb adult.

The assembly was pretty bad on that bike...I had to do all kinds fo work to it, down to deraileur adjustments right when it came out of the store. Maybe if that bike had a pro work on it, and had the brake calipers replaced with something more solid, the bike might have held up a bit better, I dunno.

On the other hand, the higher end x-mart bikes seem to be of very nice build....if the shops have quality assemblers, a few of those bikes could pose real competition to entry level bike shop bikes.

Pardon if my posts sound like a rant, it's just after my bad experience, I just have a lot of skepticism towards mart bikes.