Hello Bopupanddown,
I think the problems you've experienced could be due to the saddlesingers being fitted badly or possibly they don't fit that floyd derivative. See examples on
http://freespace.virgin.net/david.beeson/index.htm
homepage.
A set of saddlesingers, if properly fitted (is'nt hard if you follow instructions on back of pack), will last for years.
I suppose tone is subjective.
Saddlesinger users, I've heard from, all say the tone of the guitar is edgier, richer, louder and that the whole guitar resonates better and seems more responsive.
I tried some graphtech saddles on a Strat and found due to the shallow string take-off points and the poor conductive characterists of the low density graphite material they're made from, that the tone suffered enormously. After a weeks roadtest I put the old saddles back on so can't judge them on string saving.