TT mats

I use a custom made (as in I asked the guy to reduce the diameter) acrylic mat topped by a  Teac Washi  https://www.musicdirect.com/accessories/TEAC-Washi-Turntable-Mat
on my Oracle Alex III with an aluminum alloy platter.
I tried the Acrylic because that's what Oracle has switched to. It proved to sound somewhat cleaner than the Groove Isolator that I was using. Still, I didn't have the nerve to clamp mt vinyl down on such an unforgiving surface. Hence the Washi. 
These days I remove the Washi when playing 180 g LPs and clamp ever so lightly. This compensates for VTA (I tell myself ;^).

Anyway, it sounds very realistic and 'present' to me.

Combak Harmonix tu800 ex. It's not the i(improved) version. It came with my table along with the turntable weight. I think it's a VPI. Has two rubber bands on it. I took those off a couple days ago. I did notice a little more livelyness for lack of a better way to put it. I have been wondering about the mat and trying something else. A 10" record sounds like a fun and inexpensive experiment. 

Herbie’s Way Excellent Turntable mat!!!

http://herbiesaudiolab.net/ttmat.htm

Don't spend $400 on a mat.  Get the Herbie and put the rest towards a Stillpoints record weight.  Now that takes out the micro-resonances!

I use a FunkFirm Achromat 5mm in combination with a flexible, 1mm thick material I happened across, no weight/clamp..perfect!!!

Relegated my Stillpoints LP-1 to the top casing of my phono-stage.

I have a VPI Prime Signature. I could not stand the "hard" sound from the bare platter. I got the 3mm Achromat, I use the peripheral ring and the sound sweetened up and became more musical. VPI claims the paper shipped on the platter is supposed to be used as a mat also. I don't know what they listen to, but I want musical music. I had heard about the Achromat on many forum threads, but Michael Fremer's review was what sold me.