I have a Givi E52.
For my money it’s the best as it is the biggest available with the soft backrest attached by wife finds it much more comfortable to ride with me than without a backrest.
I bought the black one that comes with the lights installed because you get the lights with it already installed for less than the coloured boxes without lights.
However, I discovered that you can’t depend on the lights. Apparently they are incandescent mini bulbs instead of the LEDs I was expecting and don’t last. One of them was burned out or broken within weeks of me getting the box. The connection to the wiring system – so you can easily remove the box from the bike – isn’t the best either as people would often tell me my brake lights on the box weren’t working, so when I transferred the box to my Exec I didn’t bother with connecting the lights.