I have one, but it's in a drawer now because I was finding it too difficult to switch between it and a normal laptop keyboard. I want a split keyboard that has all the keys in the same places, so muscle memory doesn't need to adapt. I touch type, so the same fingers just need to find the same keys in the same relative positions. Mainlander does not do that, and I can't find the layout or top view zoomable photos for this one :-/
I switched to Microsoft Sculpt for this reason. Muscle memory is fully compatible with a laptop keyboard. Except it’s much more comfortable, due to the tilt, width and superb tactile feeling for such low-travel keys. Totally took away all my wrist pains.
As a bonus it doesn’t look like a science-lab on your desk, like a lot of other ergonomic keyboards do. Got to say this new Advantage 360 has a really nice look though.
There's a ~$30 add-on accessory to add tenting support in 5°, 10°, and 15° positions. Same as with the Freestyle Edge mentioned in the other comment, for the newer, gaming-focused keyboard. I find it to be the best part of having a split keyboard.
And its also distinctive because you can (with some caveats) use separate USB cables to each side, rather than a cable spanning the two parts. That works really well for me.
