Floating Floor Materials

We're getting close to order all the materials and I was wondering... why neoprene under the floating floor? Are there particular properties of neoprene that lend itself to being the perfect material for this application? Are there alternatives? I know I've seen some various materials used in the homerecording.com forum and in Studios under Construction.

Neoprene is just a synthetic rubber so rubber is the alternative. There's a page showing how we used rubber on this page: http://johnlsayers.com/Guruland/Pages/page2.htm cheers john