The mat, any mat, will have a major if subtle effect on sonics. In the end, there are many "good" choices depending upon one's personal preferences. Try a few good candidates before deciding, is my advice. On my Denon DP80, I found that a Boston Audio Mat1 was "better" (to my ears) than a Herbie's mat. The only generalization that applies, IMO, is that the stock rubber mats of yesteryear, the ones that typically were supplied with Japanese DD turntables, can easily be bettered. If you want to try a metal mat, I advise you to choose one that is not much heavier than the OEM mat, so as not to screw up function of the servo speed control mechanism, which is tuned to the total mass of platter plus mat.