Due to the current absence of a mount system (except the lanyard hole), I am interested, which mounting solution/ideas you have found for yourself. I really hope that Garmin will offer something like Zoloe does soon.
The messenger is: 7,8 x 6,4 x 2,3 cm. Because I don’t already have my device, I used somthing with s similar size (hydrometer): 7,7 x 6.5 x 2,2 cm. This is an old MFH Molle Handyhalter, (tactical), which was laying around in my drawer. It fits perfect. You can put it on a belt or on a backpack strap (horizontal or vertical) and one pic I have added an additional carabiner. You will have easy access to the messenger and I think because of the open structure of the pouch, the reception will not be disturbed. The price for the pouch was about max. 10€ (years ago).
After my messenger arrives, I will exchange the photos