I have an Acoustic Signature Samba TT w/a modified Rega 300 and a Denon DL-304 cartridge. I replaced the stock felt mat with an Oracle groove isolator and it was a huge improvement.
What mat for aluminum
I have an acoustic signiture final tool TT. I have found that The Extreme Phono donut with fiber mesh and a Sumiko thin fiber cloth on top sounds best to me. I have tried The $100 paper mat. This combo brings out the details. Lets keep this discussion to metal platters.