For the last week I've been commuting in temps of lemmesee.. 10-14 F. I wear mediumweight wool socks, winter Shimano shoes with wool inner soles and neoprene booties. If I remember to pedal "round", and not mash my toes down all the time, this is ok for rides of 1-1,5 hrs. If I forget, my toes go numb, and once numb they're impossible to heat up again. I used chemical warmers one day, but had to go to thinner socks, all in all an expensive and not that effective solution.

But closing my neoprene booties UNDERNEATH my AmFib tights instead of over them made a noticeable difference. The booties are a bit snug around the ankle, and the added pressure cuts blood circulation just a tad. The tights are stretchier and go fine on top.

Below about 25 F I wear PI lobster gloves.