I don't use my BMW top box except when I need it for hauling a bit more stuff or when the Mrs. rides pillion. Even well loaded down I really can't feel the difference on the bike with the top box. At least up to slightly above 100mph I don't feel any buffeting back there. I'll be doing some touring this summer which will be a big change after my Goldwing but with the seat and top box I believe there's about as much room for carrying stuff inside as the big Wing had. I like having everything secured under lock and key. I usually keep a 12V inflator, tire plugs and tool, roll of TP in a waterproof bag, LED flashlight, bath towel (for wet seats), Frogg Toggs and a leatherman in the under seat area. Those pack in the box pretty without using up a lot of the available space. My bike came with the BMW box and backrest, I would have purchased the SHAD if it was my money but the color matched panels on the BMW box do look good. I'm thinking about adding LED brake and turn signal lights on the back of the box to improveir the visibility to motorists.