I Bought this lens last December after reading the reviews on this site.
My copy is a DG version, lens and build quality are VERY good.
Sharpness is very good for such a great range zoom.
Found it very useful in outdoor shooting and sport in sunny days.
F6,3 at 500 is a bit slow, but it's good for the price (500mm F4 cost a lot more!).
Worth every money spent and MORE...
Thanks to everyone who posted a review for the Bigma on this site!