Don't know specifically about that company, but in general aftermarket body parts don't fit as well as the oem ones. This pertains to specialty car parts as well as fenders and other body parts for current cars. At the body shop where I worked we would only use factory parts because the body techs would have to spend so much time fudging aftermarket ones to fit. Some insurance companies would only pay for aftermarket parts so we would fight with them to get oem replacements authorized.

A few weeks ago I was watching a tv car show where they were restoring some classic car and the guys doing the job were complaining that the aftermarket fenders, hood, and bumpers were tough to get to fit correctly and needed massaging.

Don