So, Brad has pretty much talked me out of putting the "G" cams in the 996, at least for now

, so I'm making the 996 my 'sport-touring' bike and will save the 999 for less than 3-day rides, Sunday mornings, and track days.
I've replaced the mono seat with a biPosto seat and subframe. Am wondering if any of you biPosto guys have some recommendations for a bag to mount on top of the passenger seat. I've a Marsee Anton Borsa tank bag that works real well for either bike, but doesn't have quite enough capacity for a 4-day trip that might involve significant quanitities of cold and rain, like last year's trip to Big Bend featured! [But last year I had the ST2 and two really nice saddlebags!]
This bag would mount SECURELY to the passenger seat, must be big enough to be useful but not so big everyone's going to point and laugh
So you biPosto guys, any recommendations?