I have very wide feet and somewhat wide calves.  I bought these boots in a size 10.  They are a tiny pit too big in length but they are perfect in width and for my calves.  I stated that they are somewhat large because they do fit my width in feet in calves.

They are VERY VERY comfortable! These are an all day boot, I wore them for about 15 hours and my feet were never uncomfortable.  The sole is a strong but "absorbent" rubber that is much more comfortable than traditional western boots and they have better traction. Also, very warm in the winter with a pair of tall socks.

I can not speak about durability since I have only had them for a few weeks.  I would not recommend buying them on Amazon unless they are being sold for less than regular MSRP which is $150, I got mine at TSC.