This one has some major CA around the white edges of the bird: http://g-ecx.images-amazon.com …_1311_06._V367350197_.jpg
I don't know. These seem like 70-300 and 55-250 IS type quality. None are bitingly sharp, just kind of average. Which is kind what I expected given the price. There aren't many (any?) other options to get stabilized 600mm (960mm @ 1.6 crop!!) at even triple the price of this lens so hard to complain too loudly.
Yea, it looks correctable though.
For many people (perhaps myself included if the AF is good), this is good enough IQ. I'll take 55-250 IQ for this type of lens because I'm not going to be spending 3k on a wildlife lens, never mind $6-12k.