> Has anyone used this stuff in players?

Why would you?  I went to their web site and found this on
their "Ecsaine vs. Suede" page:

  Air Permeability:  Ecsaine's micron-sized "pores" yield
  high breathability.

Therefore, it will not be air-tight!

Duaine Hechler
St. Louis, Missouri
http://www.hechlerpianoandorgan.com/ 

 [ I think the French firm's trademark is applied to a broad
 [ range of synthetic fabrics, in the fashion of the DuPont
 [ trademarks Rayon and Nylon.  Adverts are usually worthless,
 [ in my view.  Get some samples of different Ecsaine fabrics
 [ and -- like Craig Brougher and John Tuttle remind us --
 [ "Test, test, test!"  -- Robbie