I also got my Chinese 52cc saw today. As Stephen C. says, something is seriously out of line with the clutch cover. I'll read his post again tomorrow and try and figure out what I need to do.
The one I got also has 18 inch bar. The manual says the chain is equivalent to .325 Oregon 21BP (72 drive links).
It seems relatively light for it's claimed 52cc size. The fit and finish are marginal by western standards, but not unacceptable, except for the clutch cover.
I did start mine. It started quite easily for a new saw. It smokes a lot with the recommended 25:1 mix (actually 20:1 for break-in.) It seems to idle a bit fast, but the chain doesn't spin as it idles. According to the manual and from what I can see, the carb is easily adjustable. (Mine is labeled for Canada.)
The throttle response is great--no hesitation at all. It cut about as well as my Husky 345 (which has narrow kerf .325 chain.) I think the 18 inch bar may be too long for this saw if I were to bury the bar in a big oak log. I'll cut more with it this weekend.
I think Stephen C.'s conclusions about the saw are exactly right, so I'll just briefly paraphrase him rather than try and do better: "I would not recommend the GIO saw to a first time user without any mechanical skills. . . . The heart of the saw seems to be well built. It balances well in the hand and is very light for its size."