Other split options: https://raymii.org/s/articles/Split_keyboards_a_five_year_re...
Part of this is my weird typing style (I occasionally cross fingers over to the other side of the board to type certain words at certain times - you can't do this on a split board), and part of this are function keys and enter being placed right around the spacebar area, in a zone where you normally can just depress your thumb and not have to think about the positioning too much.
Adapting to the layout was frustrating. It took me a week of standard use to not have typos. About a month to lock down the location of modifier keys and layer layouts.
Was it worth it? In my case, absolutely. The pain in my forearms disappeared. I also type "properly" on standard staggered keyboards now.
It turns out that in my case, the weird typing style was part of why I was feeling pain in my forearms in the first place.
i recently got one, and been wondering if i should place them full shoulder width apart or not.
It costs an arm and leg and takes a while to learn, but it makes every other keyboard I've touched feel downright archaic!
If you have a modifier-heavy workload the keyboard gets lost. A few times a day I have to flip through all the modifiers to get one unstuck. Probably once a week I have to power cycle it since that isn't sufficient. there is so much room in the case I also wonder why they haven't invested a little effort and made a bluetooth with battery option - I've been sorely tempted to do this but never could justify the time.
The thing I really like* about this keyboard aside from modifiers on thumbs is that you can effectively use it on your lap and shift positions. it feels a little more like a musical instrument that way.
Something I've been thinking about getting is a clip on 12 inch monitor + RasPi, it would be such a great remote development setup for cafes.
https://www.amazon.com/Kinesis-Advantage2-Ergonomic-Keyboard...
Note that the keys are in columns and not staggered, so there is a learning curve.