These things are amazing but there are some bad ones out there. I've worked closely with the mfg to make sure the areas of concern are addressed. Stuff like, better suspension, heavy duty spokes, better air filters, disc brakes. In the beginning when I was ordering them I had problems with wheels, and front brakes. I've got all of that ironed out now and they are great.
Yes mine also have the rotary style 4 speed transmission and it's a bit awkward at first but once you get the hang of it I think it's better than the traditional shift. Just my opinion though. One of the best things is, most of the knockoffs are completely interchangeable with Honda parts. If you wanted to step up to a bigger bore, just go to your local honda shop and get it and it bolts right up no problems.. I've done lots of stuff to mine.
But the absolute best part is you can get a bike that looks identical to a Honda XR or CRF 50, but has a 72cc bore, 4 speed tranny, disc brake, better suspension, better exhaust and a lot more for only $500 out the door.. You can blow 3 of these up before you get to the cost of an XR.. I've been dogging mine for sometime, and so have my customers and noone has ruined one yet.. I've got a pro rider that has bought 2 (one for him and one for a gift) and is about to buy another. He swears by them..
They are like any bike.. If you take care of it, it will last..