I'm sure its not what you want, but I'll throw it out there anyway - - I use a T-Bag "Laconia" soft bag as my topcase. It is a rigid square in shape and beautifully made. It rests on the factory luggage rack and attaches to my Pirates Lair passenger backrest - all T-bags secure to a backrest. It comes on and off the bike in less than 20 seconds, has a handle and shoulder harness for transport, and holds my laptop and a lot of other stuff . . . . or a cooler with refreshments . . . . or a fulll face XL helmet. I do also have Givi 21 L side hardcases which usually stay on the bike, but I really like the combination of hard side cases and a soft topcase which comes completely off so easily. Of course you cant lock the soft luggage or secure it to the bike, but thats what you get for $123.00. Good Luck.Actually, I ordered that unit yesterday and was notified today that several of the pieces of hardware are on back order and may take awhile to receive. And that got me thinking about alternative possibilities that may be just as good as the setup TT is selling.
Lots of riders get top boxes and just bolt them on their luggage rack. However, because I park my bike on NYC streets, I want to be able to remove the case quickly and easily.
So my question remains - can I hybridize a top case with a different mounting system that will assure quick release? I can't imagine it hasn't been done. But with what pieces?