I have the Triumph slant leather bags. I like the look with the Triumph logos on the lid and buckles. They seem to me to be the right proportion for the bike, however they are on the small side. With them being slanted it's sometimes harder to stuff things in. For extra room I load up my gym bag and strap it across the top of the bags and pillion seat. So far, I've been able to shove cordura pants with armour into one, gloves, vest, mask, tools, water bottle, etc into the other. One other drawback, the leather over the fender has scuffed up the paint, nothing serious. It might buff out but I haven't tried.
Rich