I'm making this a separate post because there seems to be a fair bit of interest in Duo. I'm not affiliated with the company in any way; what follows are my honest opinions.

Duo boots are sized by shoe size (European sizing) and calf size (30-50 cm or 11.8 - 19.6 inch). Although I have not used their customer email service, I have heard great things about how helpful they are from some of the blogs I read. They boots are all normal width in the foot. I have normal to slightly
wide feet and they fit fine. Duo also sells shoes and ankle boots in
wide (shoe) widths but I have not tried those.

I have purchased 5 pair of Duo boots and have been thrilled with 4 of them, less happy with one pair. The pair I wasn't happy with have a defect in the heel, where you can feel the nails digging into the foot. I solved this by using a half insole for cushion. I didn't complain to the company, which maybe I should have done. Those are my least worn pair, but more because they are the dressiest of the bunch and with the highest heel than because of the defect which I was able to work around.

The first pair I no longer own because I wore them literally into the ground. I wore those puppies probably 3-4 times a week for at least 7 months out of the year for a good 4 years before the heels were destroyed. And when I say wore, I mean I really wore them - I was a student at the time and walked miles a day in them. They could not be repaired because the leather was glued to a rubber sole/heel. My other 4 pair (navy, black, brown casual, and brown dressy) have regular soles and heels that can be repaired, thankfully.

Before making the jump to Duo, I used widewidths.com. The cost was lower, and the quality, while acceptable, was also lower. However I found that I loved having knee high boots so much that I was willing to fork over the extra $$ for quality, stylish, real leather boots.

These are my 2 most worn pair of Duos. Mind, I have 19 inch calves, but these do not look like fat lady boots. Or if they do, I don't want to hear it!