[Panzermann]

Givi has two lines of Top cases, Monokey which is the larger and tends to be styled for larger bikes and Monolock which have simpler styling, are lighter, and geared towards smaller bikes and scooters.

The Monokey also have a higher rated load

 

[Backonaboxer]

If you're set on a Givi box, ignore this.
If you're open to other brands, may I recommend a Shad top box. Quality is comparable and one notable feature: you don't need the key to open it. If you're in and out of a top case often, it's awfully nice not to have to pull the key out of the ignition, stick it in the box, then put it back in the ignition. Of course, it's also lockable. I just hate keys. Once you get used to that feature, needing the key every time on another brand is a real PIA.