"The trouble is getting the pads stiff enough to last with the force of the crossbow, but still soft enough to absorb the viberation in the string"

Yeah, you hit that nail on the head!! Seems like Horton found that out the hard way on their new recurves. Remember the trouble scpatterson had w/ his? Pads ate the string!! Then when they don't eat the string [softer compound??] they fly off the arms. They may have solved that problem by now, but it had been going on since the ATA show last January. I'm also of the opinion that if something worked well Bill T would be on it like a chicken on a june bug. I tend to think too much which gets me in trouble some, lol, but I recall him getting close to 250 fps w/ 900 gr arrow out of an Emax on his elephant. I tend to think [look out] that if a guy was a quiet fanatic, one of Boo's Excel strings w/ served cat whiskers and about a 500 gr arrow w/ 2" Blazers and a good mechanical would be about as quiet as you can get both in bow noise and arrow flight. Just a hunch.