Ok, I purchased the Badgcustom solo bag for my Dyna, it didnt take but a ride or two for me to realize a couple little faults. The bag itself is an excellent bag, but it lacks rigidity. Also the flap needs held down in a third place up front.

I work for a company and our business is brass, what i did was find some strip the right width, (plastic and a heat gun would work as well as heavy flashing would work)
i measured the bag, cut the strip to length and started bending. leaving it a little big so it would spring out to stretch the top of the bag. pictures below.
As far as the flap, i just added a snap. The bag is completely empty and holds its shape, the flap dont blow around.
The reason im posting this is, im seeing this same bag on other bikes and it looks terrible when it wont hold its shape, and its such an easy fix.