copper platters vs. carbon fiber platters vs.?

Hi all!
Have noticed the large amount of these type of aftermarket platters in the last several months..Some even have the two materials bonded!
Are people after the TWcoustic approach or are there valid reasons for these new products?
Do they indeed enhance or replace rubber mats?

Thanks to everyone
I assume you reference the TWacustic due to the copper platter in their high end model.

In my system the mat is almost as big an effect on sound as the phono cartridge. I have the newest Ttweights copper mat, the Boston carbon fiber, The Funk Firm, the last version SP10 MK3 mat, a Micro Seiki CU-180 and the dual layer Ttweights Micro Platter.

So far the Micro Seiki CU-180 is my favorite but they are terribly expensive. I've seen the CU-180 go from $450.00 two years ago, to $800.00 and more today. This evening a search turned up a NOS in original box for $1160.00 plus shipping.

The Ttweights may or may not match the Micro Seiki CU-180, but one thing for sure, it's a drop dead bargain compared to the competition.

I spoke to Larry of Ttweights last March at the Canada audio show, other than that and having bought some product I am not connected in any way.