No. I bought the sandstone previous to the Minus K as I had horrid feedback issues with this TT.
A fried lent me 4 small mudstone tiles and they fixed 90% of the issue, so I went one better. It was cheap (under $200 from memory from Gosford Quarries in Clayton, Vic.) and is the same sandstone as they run under all their test gear at Monash Uni, so I figured it was good enough for me.
...Then the Minus K turned up. What a revelation! Instant noise floor drop - even a half going deaf old fart like me can hear it. But the best was how the soundstage was no longer 'homongenise. All the players and instruments were more on their own and a beautiful smoothness to everything. Only problem is my Minus K is rated for around 38kgs and my TT is 36kgs, so it's really on it's limit. I might have to look at a bigger model down the track.
As I said before - now to fix everything around it!