Remember if you are in the lower end of the 5’6” to 6’ range, a ¾ length UQ might be essentially full length. Those shorter styles are easier for me to set up because the loft is concentrated where it is needed. Usually the TQ design is sufficient to keep what ever part of my lower legs need the warmth - or just use a small pad at that end. The smaller UQ saves money, bulk, weight. But of course it has to be able to do the warmth job too.