The GergoPlex is (I think) the keyboard I would most like to try using.
It looks like this:
It’s not a stenography keyboard (although if you peruse the rest of the g Heavy Industries website you’ll find the Georgi which is), but it is ortholinear and split in half, and I think I would like it a lot.
I’m really just adding it here so that I can find it again – it’s sold out at the moment – and because I love the design of it so much more than I have of any keyboard I’ve ever seen (most of which are, in my opinion, hideous).