I bought a pair of these a couple years ago and they seemed too much trouble to use.  But it was icy out, I wanted to take a walk, and I thought I'd go through the problems of getting them onto my boots.

The size I bought was S, which should have fit women's shoes up to size 9.5, but was too small to get onto any of my size 8 shoes except for a pair of dressy boots I wouldn't have chosen to use for a serious walk (no support, plus too tight in toes).  They were a real pain to put on the dressy boots; I needed to struggle to stretch and stretch them.  Plus I needed my husband's advice to figure out how to put on the strap.  However, I managed to put them on the dressy boots and was able to walk with confidence over icy sidewalks.  so, yes, they work fine.  But order at least a size, possibly two sizes larger than the manufacturer suggests, unless you enjoy shipping things back for returns.

Basically happy; wish I'd ordered a size or even two bigger.