what would be a good mat for a VPI SCOUT JWM9

No, and none. The acrylic platter/clamp system are designed to provide you with all you need for great playback. Most aftermarket mats are designed to compensate for a platter deficiency.

thanks very much Slipknot1.pat

I have a VPI HW 19Jr and I agree with Slipknot1, no mat. I clean the platter as needed with a very soft, lint free cloth and old fashioned, no additives, windex. It works very well.

I actually tried a mat because I had one from my other TT and agree with above it made the sound worse.

Sorry to have to disagree here, but both the Scout and ScoutMaster will benefit sonically in a very large way from the use of an aptly named product called the "Way Excellent Turntable Mat" from Herbies Audio (http://herbiesaudiolab.home.att.net/). This simple, inexpensive mat ($50) transforms the midrange to richer, warmer, closer to live music better than anything else on the market. It's so good that you will probably stop using the clamp unless the record is warped.

Wow. That's a lot to ask of a $50 mat. Anyone else experience this?

Nope. Tried felt, Sorbothane, Herbie's (btw, am a BIG proponent of the Grungebuster for CD's though). Mats on the Scout/Scoutmaster deaden the sound and muck up the pace and drive. Harry Weisfield designs this way for a reason. Give that platter a hearty rap with your knuckle (without a record on it, please). No ringing, no feedback.
Nuff said. But if anyone insists, I have a 95.00 Audioquest Sorbo mat I'll let go for a low low price....

I have a Herbies way excellent Turntable Mat
& have used it on my VPI TNT with the newer inverted
bearing all acrylic platter. I like the sound better
without it. I do have Herbies other products & have
had very good results, but I think the VPI acrylic platters
are pretty good & don't need a mat.

thanks for the input everybody, i think that the camp of no mat has won.pat

Yes, without mat is better for VPI.  I have a scout master with acrylic platter.  using Pro Jet Cork mat on it and reduce the resolution, lessen
3D imaging , more fuzzy,...
don't use any!

I have an MMF-5 with plastic platter and felt mat. Based on tweak reports, and since it’s cheap, I just bought a Herbie mat that’s not arrived yet. As it turns out, I’m looking to get a new TT, and I’m considering a VPI Scout, Prime or Signature. From what I read, they all have Aluminum platters. Thus I’m confused when you guys talk about acrylic platters on VPI.  Could you please enlighten me?
Sorry for the newb question, and I don’t mean to hi-jack the thread.  Apologize if this question is doing so. 

I have a Superscoutmaster......no mat- much better.  However, I switched to the Classic platter....now THAT's an upgrade.

the acrylic sounds great by itself with clamp.