I've tried the shorter knee warmers and, at least for me, they just don't stay in place well enough, plus they don't cover enough of the legs to make a heck of a lot of difference. These Garneau leg warmers really do the job. They are thin but really keep the legs warm with a soft liner. Perfect for spring and fall mornings with chill in the air.
These work very well to keep your toes warm in cold, dry weather when you don't need to wear rain booties. Easy to put on. The only downside is the wear on the bottom, but I think this is the case with any toe covers.
Bought this to wear on early morning commutes below 40 degrees. So far very happy with the product. Keeps my forehead and neck warm and absorbs sweat well. Would definitely recommend for colder temperature riding.