Just a little fyi, after spending some time with my wood stem, I'm considering making wood stems as an add-on for the Nomad II's.
The design I've chosen is pretty much a replica of the glass stem, except the internal diameter is slightly larger, making the walls a bit thinner... but the herb chamber larger as well.
I put a slight taper on the ends of the tube, on the inside. This gives the opening a very slight flare outwards to perfectly match the slight taper of my basket screens. The result so that the basket screen pops in the end of the stem effortlessly... and doesn't cock sideways at all. With a light touch, it stays in place, and when it's time to unload, the screen pops out effortlessly as well. This makes the unloading tool that I use with my glass stem setup unnecessary... which admittedly makes the entire package more portable friendly.
This is an unexpected, but welcome advantage over the stock glass stems.
I have also loaded my wood stem up with glass beads, and this has proven to be just awesome. Of course, you can change the amount of cooling by adding or subtracting cooling beads, so that's fun.
And as a side note, the all-glass cooling stems from Dave are also awesome. Same great cooling effect, but the pure taste of glass... they look really neat as well.
Anyhooo. I originally thought that I might just use roasted maple, but now I am thinking that there's no reason I shouldn't test out fruit woods. Fruit woods are generally considered safe for food contact items, and in tobacco pipe making. So, woods like cherry, apple, pear, apricot, etc.. and their burl woods, could all make great stems.
I have some pin/choke cherry burl that I harvested a few years back, they're dry now, and I think they'll make some very nice stems. The wood is very hard, very durable.