What are the "must haves" for a lot of riding?

[Django]

I don't like the magnetic, as they tend to lead to a scratched tank somehow.

I ride a Held tank bag, which uses a belt around the headset and a velcro at the rear to be attached to the tank.



When not using the tank bag, the pile site of the velcro is stowed invisible under the seat.



It is folded under the seat.



When I want to ride my tank bag, I can unfold the pile site



Then, mounting and unmounting the tank bag, e.g. for fueling, is as easy as with a magnetic.



By the way, at the first picture you see the tank bag in its smallest size. It can be enlarged very easily to nearly double height. It's compressed by a simple zipper which curls around the top.