Well speaking as a person who bought two new chinese dualsports in 06 all I can say is I wish I had just bought new/used brand name bikes instead.
I spent the first summer redoing the engine mounts on ours because of the shoddy workmanship and terrible materials used.
The electrical wiring is problematic.
I did finally end up with solid decent machines but looking back I realized it wasnt worth the few bucks saved.
Although I have read that the quads have gotten a little better but I wouldnt buy one unless I could see it in person but even then with it being chinese and little to no support it just isnt worth it.
for a grand you can find a decent older quad that may or may not need much but in the end will give you far fewer problems and have much better parts and service support.
I did put an extra 200cc chinese engine I had in this old blaster.
I have less than $1K in it and it works great but it took a lot of work to get it done.
The chinese engines run OK but most everything else is junk.
I dont expect the engine to last anywhere near as long a a name brand engine would though.