I personally am not a fan of trem nuts. I used one on my S Hollow and it sounded dull and muted. The material is very soft. It worked well and kept excellent tune for a a while, but I used the trem a lot and wore it out in about 6 months.

I'm a fan of good old-fashioned bone. It provides a great tone and is very long lasting. It's hard, so the strings don't wear grooves as bad. I use a bit of graphite to lube the slots and my guitars stay in tune well.

As Ben said, it's worth it to spend a little extra money to have a talented pro cut the nut.
--Garrett--
G-tars