I have a PMR30 and a KSG. Early problems with the PMR with FTF's every 2nd or 3rd round - factory replaced slide and barrel. Great concept gun, but IMO too closely tolerance and finicky to be a carry weapon.
The KSG is a great concept but there are idiosyncrasies with it that I don't particularly like. I took a look at the new KSG competitor from DP (online) and it seems to be something I'd want more than the KSG.
Friend had a PMR and found it to be unreliable. He rarely gives up a gun once he has it, but couldn’t get rid of his fast enough. Hope yours is doing better.
Thanks for mentioning that DP shotgun. I never knew it existed: https://www.youtube.com/watch?v=XzAaTcOdt6Q