I’ve been using mine for a little over a month now and have not gotten any imprint on my California Poppy leather case. Maybe because there is no charging current passing through the case, but thats just my guess.
I have a knock of magnetic car charger from Amazon but I don’t want to try my case on it if it will leave a ring. Has anyone tried any with a built in charger. It’s basically the same deal as the Belkin just with charging capabilitys