To Teajay,
I use the thicker one that measures 1mm thick.
I did not notice any sonic downside with the Boston CD Stabilizer and found the flow of music to be more natural. It is not a flimsy CD mat that can get crumpled like Marigo's etc. It forms a very airtight connection with the CD below and forms quite a rigid clamp with the Accustic Art magnetic CD puck on top
To Tbg
Sorry in my haste to reply, I accidentally kind of portrayed the Boston CD stabilizer as a replacement puck. It is not meant to be a replacement puck, but meant to be complementary to the existing magnetic puck in clamping the whole surface of the CD down. By extending the clamping area of the original CD puck, it should prevent flutter of the CD at the rim when it spins. The idea is not new actually, in Japan one can buy a similar CD stabilizer made of Carbon fibre (Boston uses graphite) that comes with various thickness too. Yet to get my hands on those for comparison. More info on the Japanese equivalent can be found at
http://www.phileweb.com/shop/begins/
(look for CDS-1, can use Babelfish Altavista to translate)