I have several basses from Andrew Drake of Drake Custom Bass. My most recent builds from him have been from roasted woods. In those basses we've worked with Maple for both neck and body woods and Swamp Ash for bodies.
With roasted necks, if the roasting is done well, you can leave them unfinished and apply wax, buff to your liking and get, in my opinion a very nice feel. Roasted necks are very stable and require little or no adjustment unless tension is changed appreciably with restringing.
I find tone and sustain are enhanced in my roasted basses. But, of course, that is very subjective as we all hear tone differently and, as a result, will have different thoughts about what we like best. For me, the combination of roasted Ash bodies and roasted Maple necks with Ebony boards delivers more clarity and punch. I also think the sound is a bit more organic, particularly with my fretless basses.
All this said, roasted woods do not present "do it all" solutions. The right combinations of finish, electronics, ergonomics, hardware, strings, and amp and cabinet selection are additional pieces to the puzzle. Lest we not forget time in the 'shed.
The things I've described here are the result of years of experience before I have finally become comfortable with my preferences. What works for me may not work for someone else, again, because we all hear and experience things differently.
For what it's worth, Drake has told me multiple times in recent years that he now prefers to build using roasted wood. He has a great supplier who conducts the roasting process himself. He believes roasted woods are more stable and easier to work with. He believes roasted woods deliver superior tone and sustain. He has a very high level of satisfaction from his clients, but especially so from those for whom he has built using roasted woods.
A previous poster stated that the roasted woods smell good. Indeed they do. Frosting on the cake.
If I'm bass shopping, roasted woods always get more of my attention.
Hope this is helpful.
Koog
Note: Edits are to correct typos....grammar....spelling.