El Lawrence is the last of the dark colors for now. It's not quite a black, but it could be mistaken for one in the right light. It's actually a dark green/black that looks like motor oil. I'm pretty sure I heard that description from Brian Goulet, and it's spot-on. It's a really interesting ink, and it's one that is certainly worth having in one's collection.
It's well-behaved on all sorts of papers, and it does some shading on most of them. You can, of course, see the shades of green on Rhodia.
The one negative thing I'll say about El Lawrence is that it tends to dry really quickly on the nib. If you're leaving your pen uncapped for any length of time without using it you should expect a slightly difficult start. Once it gets going there's no problem, but that first line is liable to skipping.
Is it water-proof, you ask? Well, see the video below.