I have been using the current Marigo Audio Lab 3-D mat, v2, and although it is $95 retail, well worth it to optimize CD sound. Marigo indicates their Marigo Signature 3-D mat is even better for $199, and with a birthday coming up, who knows? :>)
By the way, through an Audiogon buy, my mat was $50, although this new model rarely for sale on Audiogon.
My previous Marigo Orpheus Crossbow CD mat certainly helped, but the latest is the greatest, a real upgrade, not merely a higher price.