Hi all,
I just returned from HK and got my copy of the 24-70 HSM. From my usage while I was there, I can confirm that my copy has a back focusing issue at 60-70mm wide open, and this gets apparent when the subject is approximately 5m or more away, slight softness when the subject is around 2m away, but sharp when taken close up. However, once stopped down to f4 or f5.6, the lens is sharp, very sharp.
I'm intending to send the lens for calibration just to make sure that this lens can actually perform well at 70mm wide open, otherwise, it's gonna be quite a disappointment.
Just a side note, I paid HKD 5,700 = SGD 1,030 from a shop along Nathan Road, Tin Cheung's price was HKD 5,500 but they were out of stock, and other places were quoting above HKD 6,000.
Cheers!