Yeah I found it very painful at first (like learning Vim but perhaps 5x times worse). I highly recommend using typing.io to get used to it. Since the training examples are source code, it ensures you get exposed to special characters, which is crucial if you're using your ergodox for programming.

As you can see from the table on my GitHub page, progress was slow and took several weeks to reach baseline levels. This was from maybe 45-60mins per day of dedicated practice. I see the time investment as having paid for itself tenfold already.