I have a DM pad. I held off for a long time because it was expensive, and because I heard it was just a 3M doormat, and I had previously had a knockoff which was horrible. There are no words for how unpleasant that thing was.
Then I came across an actual DM sitting in a shared tackroom, and I picked it up and messed with it a bit (bad me), and it was much much nicer. It was actually soft feeling, and didn’t make me cringe to think of it on my horse’s back.
Doormat? Maybe. I haven’t seen a doormat made of this stuff, I have seen some that are more like the knockoff material (doesn’t mean the other doesn’t exist of course). So maybe the stuff at the hardware store is the same, but maybe it’s not. I’d get my hands on the hardware store stuff and play with it first, then get my hands on someone’s DM pad and mess with it too, see if they’re the same and if you could bring yourself to put either one on your horse’s back.
The DM sure does keep the Skito pad nice and clean, though. It also helps reduce the head buildup under the pad (the one thing I don’t like about Skitos is that it can get real hot under that foam. My horse is actually comfier with the DM).