My -12 is a 2016 and I'm the 3rd owner.
Ditto the post above, I find very little maintenance other than scheduled oil changes, lubrication every couple months, ELT checks every 3 months, monthly Dynon updates and a few simple recurring SB's. I've owned a bunch of planes over the years and so far the -12 is by far the easiest to maintain. Most of the action happens during the C.I. once a year. I spend far more time flying than doing mandatory maintenance.
Having flown radials for quite a number of hours, I still have to get over the idea that no oil dripping doesn't mean it's out.
I do like to spend rainy days opening things up and inspecting just for peace of mind, but I have yet to really find anything.