In reply to Ksop:
Don't worry, it is probably that the superfeet are just not right for your feet/boot combo. I bought some new boots(B3), and they recommended the superfeet green, and in the shop they felt great(better than without), and general wandering around they were fine, but on the hill they crippled me, in just the same place, thankfully no blister, just extremely painful to walk, especially downhill. Gave them a sand down, no luck, returned them for a full refund on the 60 day comfort guarantee.
Have since had numerous days out, couple of weeks climbing in scotland, many weekends in wales/lakes, and the boots have been brilliant, so the superfeet greens were clearly just too much.