I've used kymcopartsmonster several times as well; they are a tad slow (I imagine its because the parts are drop shipped and not stocked), and if there are issues they take a while to get back to you, but they eventually do. For instance, I needed to replace the exhaust pipe on my XC250, and the new pipe had a different flange on the end than the pipe I was replacing.
To make a long story short, Kymco had changed the exhaust pipe assembly (probably to stop them from cracking, like mine did when I hit a pothole at 70mph, because the new flange is about 3x the thickness of the old one), but the online drawings were not updated; they still showed the old exhaust pipe, and the old exhaust stud bolts, which were far too short for the new exhaust pipe assembly. It took two or three rounds of back and forth before they came back to me with the information about the stud bolts (as I was exceedingly concerned about replacing the stud bolts and putting on an exhaust pipe which may not be geometrically correct for the bike - a surefire way to repeat the problem). I've put a few thousand miles on the bike since, without any exhaust problems, although I'm in line to replace the stator and the battery when the weather gets warmer, as I was getting the battery voltage low lamp on a battery which was about 6 months old when the light turned on.