I have a Fitco 6-24X43 that I bought off a CGN'er here.
I took it to Listowell and it walked all over the pace on my Stag.
I have a Samson free float front end on her and someone here gave me some advice, that I shuold make sure the scope is mounted ONLY on the upper, and doesn't sit on both the upper and the front end.
Well, I had it out to the range on the weekend and it's dead-bang. I am going to take it out again, bolt it down and see if it will walk back to zero (you know, adjust 4 clicks down, 4 clicks left, 4 clicks up and 4 clicks right and see if it's still on zero.)
For now it's OK with 300 rounds of 62 grain through it.
I think the problem with chinese knock offs is they have a wide range of quality. IF you get a good one, it's really good, if you get a bad one, it's a spotting scope and nothing more.