I use my Ortlieb panniers on a number of different racks. Sometimes I need the lower hooks on the upper track of the QL2 mounting system and sometimes on the lower track. The trouble is this switch takes some tools and 5-8 mins of your time - too much hassle for a quick run to the grocery store. So I ordered an extra set of hooks and put two on my panniers from Wayne at he Touring Store. They adjust without tools so you can dial them into any rack in seconds. I use the setup above on my OMM Cold Springs racks - where I engage both hooks for uber security. Normally I'll just use one or the other.