Sock sizes are variable even in the same pair but not hugely so. I wear them all winter at night. Even in the spring and cool nights in the summer. Sometimes two pair at a time. I wouldn't be able to sleep with out them. So I'm in, probably forever. I've worn out many pairs over the years. Glad I found Polar Feet.
Regular / S (W 6-7.5 M 5-6)