I'm a recent purchaser - partly because of this thread!
FoCal says it is my sharpest lens - and I believe it!
After AFMA, I took it to the Philippines and put it to use...
Really love this piece of glass!
Nice pics, and glad you're enjoying it! Frankly, this lens alone will probably always keep me with Canon as my primary DSLR system company...although certainly there are many other reasons.