1. It's out of stock, and I don't know if Ellipse is going to make more.
2. Even if it were "in stock", it would take months (possibly/probably more than a year) to get.
3. It requires two USB cables. This is stated plainly on the site, but it's buried in the numbered list of "important notes".
I have one. Unfortunately, I haven't used it for more than a few minutes due to that last point. I had envisioned using it on my work system, but requiring two USB cables kills it for me. I don't know if the Mac is unique in this, but it only registers modifier keys for the keyboard issuing them—that is, holding shift, cmd, etc. on one side of the keyboard doesn't work for the other side. For instance, cmd+o doesn't work unless the cmd key is on the right as well.
There are utilities you can install to get this functionality working, but I can't install them on my work machine (and even on my personal system, I couldn't get them to work, so YMMV). I had high hopes for this keyboard, but it's likely I'll sell it due to problems with my setup.
Mechanically, it's exactly what you'd expect: a Model F in a reasonably (if outdated) ergonomic package. While a leap ahead of standard layouts, the Ergodox has always had some pretty big flaws, especially in the thumb cluster keys.
In terms of feeling, the Model F is definitely different than the Model M. Some days I'd call it better; some days I'd call it worse. Claims that it's night-and-day are exaggerated, IMO. (I have extensive experience with the New Model F F62 and various Model Ms over the years, from old IBMs to modern Unicomps.)
I actually felt that the model M specifically gave me my first taste of RSI. The spring force is so much higher that after a while my fingers and wrists were just flatly sore.
The problems began after I started gaming on it - and I'd been using them for work for a long time before that (5 years?). You tend to push a lot and push hard when gaming to be sure they key activates, and it's not really ideal for your fingers. And yes, they're "not good for gaming" but that's normally about the deadzone and reset, not just outright causing RSI.
I ended up going through a period of trying out some other stuff, ended up with Rosewill RK9100BR, and then just went to a keychron k8 instead. I have a couple of those now.
After years of typing now I must continually adjust angle and type of keyboard to avoid stressing various RSIs too much. Standard keyboards now just hurt, even if they're nice.
I used the EnduraPro for a few years. Moved to more ergonomic keyboards (ErgoDox and now Lily58) when my fingers and wrists started complaining. Have written multiple books with the new keyboards with no pain. YMMV.
I'm in the same boat, but if Unicomp ever manufactures a split-key I might be willing to forgo thumb clusters and ortholinear layout. Might be. I do love me a buckling spring.
If you're using a PC you can likely just get 2 keyboards. It'll use a little more desktop space but you can put them wherever you want. I've found that the mac doesn't respect "left keyboard shift right keyboard letter a for a capital A" which is annoying.
That's... creative, I'll give you that. That wouldn't leave room to put my trackball anywhere convenient. In fact, nothing about that sounds convenient, but if it works for you, more power to ya.
For most people, "wherever you want" is going to be with the outside edges a bit wider than your shoulders and vaguely parallel to a little diagonal. That's not possible with really any pair of full keyboards I've ever had.
I just moved them around until it was comfortable; it ended up with them being a bit further apart than shoulder width, the keyboards certainly weren't close to bumping into each other even though they were standard garbage 101 key USB business keyboards; I think they end up about a foot apart at the closest. Give it a try.
Space them vertically. The left one to the top, giving you a space on the right for the mouse. Or the right one to the to top, then your mouse would be under it.
Not OP, but I use the kinesis advantage but if I was going to pick one again I'd go with the ergodox, also had a keyboardio but switching between types is kinda tricky and annoying
Anecdotal, but ergodox flared up my RSI terribly. I think it might be the shear size of it and overstretching my pinkies with the shift keys pulling double duty with parenthesis.
I’m now a happy user of the kinesis advantage (though the configuration software pales in comparison to the ergodox) and feel so much better.
There's a number of options for replacing the control board on the kinesis advantage (or advantage2) with one that runs QMK, providing the same sort of configurability as the ergodox, and the advantage 360 pro runs on ZMK.
I've been on advantages for 20+ years at this point and haven't had any of the RSI that prompted the switch since.
Currently daily on a 360pro. Might want to sell it or reswitch it for something a little lighter and maybe even something linear. Maybe a silent red or lf red.
I bought and returned a Kinesis Advantage360 for a Realforce R3. The R3 isn't better, but if you don't possess the requisite mechanics for their ergonomics, there's no point in buying a Kinesis.
My guess is that, for most people, myself included, once one has invested the time in learning any particular ergonomic keyboard (Ultimate Hacking Keyboard, Ergodox, whatever), the switching costs are annoying that one just keeps using it
A small number of people seem to get obsessed with the narcissism of small differences in terms of switches, or minute aspects of positioning, or similar matters, but I find that one hits diminishing returns quickly and it's less the keyboard than what's done with it.