Anyone using the new 300 f2.8 IS II & 2xIII ?

In terms of optical quality I find the 300 f2.8II + 2xIII a revelation, particularly with the slightly lighter weight and 4 stop IS. AF speed is significantly slower but sharpness is much the same as my old 500 f4L + 1.4XIII. Maybe there is copy variability but my experience accords very well with results at The-Digita-Picture.

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=117&Camera=453&Sample=0&FLI=3&API=1&LensComp=739&CameraComp=453&SampleComp=0&FLIComp=2&APIComp=2