The only catch that I know with the ChinaClone versions is -SOMETIMES- they dont actually make it into the US. USBC (US Border and Customs) has been stopping some from making it in. A few members on GMTNation had this issue.
That being said, I just bought my Tech2 a few weeks ago. Have already used it to diagnose what specifically is wrong with my Z55, and my chime. Paid 280 for it, already saved me $120 diag fee at my local dealer.
I know I will need it eventually for my Wifes Aztek, as they seem to eat BCM's. So I know I will eventually come out very ahead.
I still have a cheaper TOPDON Elite model, for MIL, ABS, and SRS codes. But for anything more than "resetting the light" I will break out the Tech2.