turntable mat for Thorens TD 850

The felt tt mat that came with the TD 850 could be part of the reason for the less lively sound than from the Rega I had before (same arm, RB300 rewired). The guys at Needledoctor seemed to think that the felt mat was more neutral than a Ringmat, and recommended I listen to it for a while before doing anything - and I must say, I admire them tremendously for not just jumping at the chance to sell me something. Perhaps I am not used to "neutrality", as I understand that the glass platter on the Rega is said by some to produce a certain brightness. Suggestions would be appreciated.