I have read through the commentary on coffesnobs.au. Apparently some of the first batch of machines were incorrectly calibrated. The problem is said to be fixed now. Not sure how that affects USA machines. Also, it's my understanding that the OPV is not hard to adjust, but for warranty reasons Breville wants only authorized service centers to readjust them.
The Breville dual boiler thread on Coffeegeek has posts from people in America who are having problems with their OPV set too high. So apparently the problem has not been entirely eliminated, nor is it limited to only early Australian machines. http://coffeegeek.com/forums/espresso/m...806#549806
However, it does sound like it is possible for the consumer to adjust the OPV, provided they are mildly competent with tools and know how to do it. This may alleviate the problem, though I can also imagine consumers breaking something while adjusting the machine, and then having their warranty denied because they opened the machine and messed with the innards.
It would be preferable if it was set properly to begin with, so people don't have to resort to opening up the machine and monkeying around inside, since the machine is apparently not designed with that kind of user adjustment in mind.