I'm pretty sold on taking this legacy on my next character. But I just wanted to see what you said first as far as elf versus drow with it.

Drows seem to utilize it nicely, and a lot of Elves have had bad things to say about it making it seem like Drow's use it better.

Voila! You have the code. Same room, lighting, etc. Which would the legacy be better on, drow or elf?

If I remember correctly, almost the same between the two, but a hair better for the dark-elf since they can have a marginally higher DEX.

Of drow and elf being optimal for dex, int, wis etc... would a duergar not see anywhere near the same benefit with a max dex of 22?

Sneak is worth something; failing that, quiet movement is also worth a little something.

Zinsizin vs. Qenorith

Both had flow/STSF.

Zinsizin had a noticeably better flow of shadows output for the better. I was a little dissapointed it didn't fire as much with Qenorith. However Qenorith built up charges on STSF faster. I preferred Zin because the charges still got built up, only I evaded a lot more between rounds to last longer.