I'm firmly in the camp that the nut material does affect the overall sound, even of a fretted note. There are so many other things in the signal path of an electric guitar that the effect can be masked, though. Think of it like an ingredient in a recipe; a little bit of the right ingredient can make a noticeable difference. I stopped (for the most part) installing synthetic nuts unless the customer *really* wants it. They pay for the part and then labor to install it, which brings the price close to what a bone nut would cost anyway. (I charge a flat rate that includes the cost of material.) Nobody ever raves about the improvement in sound after getting a new tusq or graphtech nut, though they often do rave after getting a bone nut. The pre-slotted bone nuts that are available are best thought of as rough drafts that need quite a bit of work to turn into a finished product. The StewMac ones are better than others. The Allparts ones are downright goofy. The pre-slotted synthetic nuts are "good enough," but not good. The slots for the high strings are too wide and not always sloped right for the guitar, so I generally wind up filing them almost as much as if I were starting from scratch anyway.