Sonic Barrier damping sheets vs cork


I want to dampen my Jolida J9 phono pre, and was wondering what would be the preferred material.
Sonic Barrier sheets from Parts Express or .125" sheets of cork?

markeetaux
Another choice is the lead weights sold at hobby shops and fish & tackle shops. Lead is an excellent damper, and possesses very high mass for it's volume. Pretty cheap, too.
No other comments, specifically about the merits of cork as a damping  material? 
I like cork quite a bit particularly around circuit boards and transformers. Lead not so much.