I did -not- like the Moses Graphite Jazz bass replacement neck at all.
My experience with it was as follows:
It was installed on a solid alder body with a Bartolini Humbucker in 'P' (neck) position and a Bartolini 9J in Bridge position with the strings fed thru body into a hipshot bridge.
I dropped the Moses on and the first thing that was immediately apparent was the really indistinct voice it had for mid's and really synthetic sounding highs. The low-end was really boomy as well, with very little definition. All of this was tested on Fender Bassman amps as well as various Hartke stacks and combos.
With all of the EQ'ing I tried, I could never coax out a decent tone that sounded pleasing.
In terms of feel, the neck was of course unfinished, as it's basically a slab of graphite, which was relatively smooth but was ultimately about as bulky as a baseball bat, making it a bit cumbersome to groove on.
Honestly, if you're interested, who knows, you may like it, but really, if you want a decent graphite neck, try to dig up a Modulus (though I hear mixed reports on graphite tone) or even a Peavey G bass.