I also installed the Topeak Uni super Tourist Fat Rack on my mini ST 2. There is indeed a big space between   The fender and the rack. But I use this space to install a small bag for my tools. Love the setting.

We use Sterilite 50 gallon tote, purchased from Walmart for our rad mini 4 and rad mini ST 2. We can put both our two bikes in their tote in our Subaru Forester.

I decided to use MIK system with my Topeak rear basket and they work super well. You need to buy MIK carrier plate that is installed on the rear rack and MIK adapter plate that is installed on the basket. I've got both from Amazon which total costs $55, and there is no waiting. As there is about a 2 inch thickness of the both plates, I can fit my Rad pannier bag and the Topeak rear basket all on the rear rack. See photo.

We have installed the RADmini rear rack but would also like to use the Topeak rear basket that we already have. Ideally, the expensive MRI-Denver adapter can fit our need but it is out of stock forever and no one knows when it will be back. Cascade Manufacturing produces a similar item but unfortunately it does not fit with the Topeak rear basket. We came across to MIK carrier system and thought it might be an option. Has anyone tried this adapter yet to the RADmini rear rack?

Thank you.