I have done five quilts with minke backs. Three baby sized and two twin sized. They have all washed wonderfully and the kids loved cuddling up with the softness.
I do agree with the spray basting though. I spray basted and pinned the day lights out of each one. No problems with the quilts. My LQS recommended the spray basting too. Also, all of mine had batting. Hobbs heirloom maybe? I prefer a higher loft batting anyway. All cotton too maybe. Not sure there, would have to check my notes.
I mostly used the "dotty" minke as well and have never had any problems with it. I am hand epp a gfg quen sized at the moment and want to back that one in minke but that one has to go to the LAer so we will see if that is allowed.