I'm using the Redox (almost the Ergodox layout) for about two years now and I'm a big fan of the ortholinear key layout which (at least for me) was as much of an ergonomic factor as the split. So I would not get the UHK (but every hand is different).
The adjustment is not that bad. Just know that you are forced to learn touch typing (opting for blank key caps helped me a lot with that). When you are forced you usually learn this pretty quick. Just getting fast takes more effort.
If you want to learn vim keybindings, I would stay with the usual QWERTY layout as vim keybindings are optimized around the QWERTY homerow. In my opinion, other layouts like Dvorak or Colemac mess up at least a part of what makes vim keybindings great.
Of cause you could remap some keys like HJKL (left down up right) but you would have to do so in every application you would like to use vim keybindings. And what would you do if you are editing a file with vim on a remote server?
IMO alternative layouts are a bit overrated. An ergonomic keyboard takes you most of the way. If you stick with QWERTY you also won't forget how to use your co-workers keyboard.
Way back was an iPhone app called notesy which worked pretty much the same way as nvAlt. Elements is my app of choice right now for searching/editing my nvAlt folder on the phone. (Sync backend I use is Dropbox)
This posts pretty much outlines all the things that I do as well. It is true that in going this route there needs to be a time investment at first (and some fiddleing throughout) but once you're set, there is no need to jump on to the next hot editor and learn new keybindings.
Where I disagree is the notion that a dev environment based on the terminal beats an IDE. If you are using a language with a huge (type-sensitive) API or a complicated framework, nothing beats an IDE for its auto-completion. Especially if you don't have a black belt in that language/framework yet.
You can use ctags and auto-completion plugins but nothing beats the code-introspection developed for IDEs.
If you don't code against complicated APIs, there is nothing that beats long-term productivity with a deep understanding of the terminal and an editor that is with you for many years.
Even if an IDE is the better choice for day to day work, it is beneficial to be comfortable in the terminal.
I sometimes find it hard to believe how uncomfortable coworkers are when they have to do some work on a remote server and what length they go through not to use the terminal.
The adjustment is not that bad. Just know that you are forced to learn touch typing (opting for blank key caps helped me a lot with that). When you are forced you usually learn this pretty quick. Just getting fast takes more effort.
If you want to learn vim keybindings, I would stay with the usual QWERTY layout as vim keybindings are optimized around the QWERTY homerow. In my opinion, other layouts like Dvorak or Colemac mess up at least a part of what makes vim keybindings great.
Of cause you could remap some keys like HJKL (left down up right) but you would have to do so in every application you would like to use vim keybindings. And what would you do if you are editing a file with vim on a remote server?
IMO alternative layouts are a bit overrated. An ergonomic keyboard takes you most of the way. If you stick with QWERTY you also won't forget how to use your co-workers keyboard.