It's a given that mutes are evil, but...

[schneidah]

I was gifted one by a former teacher after it had spent untold years gathering dust in his basement; came out of the bag looking brand-spankin' new. I quite like it; fits my PT-6 nicely (with the included smaller corks), is easy to handle, and gives me the nicest muted sound I've ever produced. I haven't tried the Balu mutes for comparison, but I'm plenty happy with it.