Just ask yourself why would anyone spend that much on aftermarket parts and sell it after 2 gals. Make sure you are able to ride it in an area where you can really put the bike the through the paces of reving, shifting, and braking. The pipe and silencer maybe nice additions although some will disagree. The TAG bars maybe better than stock. Alot of the other stuff, IMO, doesn't amount to much other than looks. I doubt if the chain is 520. 420 is stock and some people upgrade to 428. I paid 3,300 for new 2005 kx100 stock if this helps you any in your decision.