It is my understanding that Rega specifically designs their tables to only be used with their own felt mats, and no other weight added. My dealer has done countless A/B comparisons with their felt mat and something heavier, and swears that in every case, people preferred the Rega felt. Since he does sell other mats, I tend to believe him, since he does have an interest in the other side of the outcome. I just use the felt on my P5. I did not find a clamp to be helpful.
