Yeah it'll be interesting to see if that's just a one off. Olympus don't tend to get any issues with front or back focusing but I often think that may be down to the slightly slower AF. When it's as rapid as the SWD lenses then maybe there's more opportunity for that - though I've found the 12-60mm to be very accurate so far. As far as sharpness goes, I find my current 50-200mm to be very sharp. I did a comparative test at 50mm of this lens + the 50mm f/2 and others and it's amazing even wide open:
http://photocamel.com/forum/blogs/pa...-shootout.html