While on the subject, my understanding is on sizes (and this seems to be confused by a lot of people)
Semi QH bars are usually a width of 6 3/4 inches
Quarter Bars are usually a width of 7 inches
Full quarter bars are usually a width of 7 1/2 inches.
All that said and done, I tend to find fit varies so much from different brands (a bit like I prefer Wallis as I am a size 14, but don't do New Look as I am about a size 18!!!

). My saddler made a roping saddle for me at 7 3/4 inches, that extra quarter was perfect.
I tend to prefer the Fabtron and Circle Y Part synthetics to Wintec if I want to give my shoulders a rest!