Bought the 6W in gray.  Here are my stats: foot size 6M, calf is 14.5 inches wide, calf height is 17 inches from bottom of my kneecap to the floor.  So I am a small person with muscular legs.  Bought this model in 6W because this brand seems to run narrow all around.  Footbed is quite comfortable, and boot is nicely fitted even around my smallish ankles (7 inches circumference).  There are a couple of things that prevent a 5 star rating for this boot.  The shape of the upper part of the boot is a straight flare up and out, the soles may be slippery on some surfaces, and the material is definitely not leather but acceptable.

The shape of the boot is important because that's probably where the 16 inch boot opening number comes from, it will not fit a person with an actual 16 inch calf circumference (at size 6) unless this person has really long legs.  In truth, it is pleasantly snug around the widest part of my 14.5 inch calves. As for appearance, I decided to modify the boot - for $36, I figured I didn't have much to lose.  So I made an inch long slit on the outside at the top of the boots, overlapped the edges and crazy glued them together to create a closer line to my leg. Once it dried I went back with needle and thread to secure the alteration, and now I have a pair of comfortable and tailored gray boots.  Once I add some non-slip tape to the soles, this will be a good addition to my wardrobe.