I personally wouldn't use the felt mat. It's a static producer and a dust magnet. It does little to nothing to decouple a record from the bearing. I don't subscribe to the camp that believes since Rega supplied a felt mat that it's the best mat for that tt. I have a customer with a RP10 who uses two MyMats and he's very happy. I have an Achromat (5mm) and really liked it on my Townshend Rock 7.
There is a new Destat III at www.partsconnexion.com fro around $270.00 shipped