I like graphtec, but I have an Earvana too, it works making th tuning better across the range, but it's not as good as the graphtec tusq nut. Not as clear.
Apart from floyds, all my nuts are Graphtec. Oh and teh gordon smith with a brass nut, it sort of 'sings' may be the guitar, but it's a warmer more sustained tone, but rings too....