In your example of NFEC, it's PEG is kind of misleading with a company that is expected to have 100% growth yoy. Unless they're expected to continue 100% yoy growth in the future...you have a PEG of .12, so if a PEG of 1 is ultimately a well valued company, this should be trading at close to 8x current share price. However, they have a PE of 12, and if next years growth goes to something more like 25%, then you have a stock trading at a PE of 50 (after the 100% growth) and now growing at 25%, so the PEG is suddenly 2 as growth slows.
I think PEG should be calculated based of a longer term growth rate instead of one year, which could be just an anomaly due to an acquisition, new product, etc. If NFEC is expected to continue growing 100% yoy, then this is absolutely correct. However, if it's not a sustainable growth rate then you have to take that into consideration and not expect it to achieve a PEG of 1.. Obviously, it's difficult to know what these companies are going to do 2 and 3 years out, but based on past growth rates you can estimate reasonable growth expectations for the future..
Note, i have no knowledge of NFEC and have no idea what its expected future growth rate is. Just when you see 100% yoy growth, it's typically not sustainable for multiple years even in our Chinese small caps. Thought I'd throw that out..eat me alive if you want. ;-)