My GTC TC-1004 chinese junk unit on a ironic GX390 pulling my 245lb fat a$$ around has been flawless. I was told by several resident experts that it would just shred belts. Speaking from experience and actually owning one its a very good unit without any issue. I guess I got lucky:shrug:
I am building a 8hp Briggs up on another scratch build up and have ordered the superior in quality TC-2 Comet. It uses the same belt the junk GTC unit uses and most of the parts interchange. I hope to report the results of the Comet as favorable as the junk "GTC" has been for me.
btw: My entire family inlaws and outlaws was riding this over the holidays and I would guess so far we have maybe 8-10 hrs run time on this bike. The belt looks like new and this mini hauls a$$