I didn’t use them a lot, but I kept coming back regularly to check the minor differences with the official book, and to get another perspective. A few days ago, I’m not sure when, the author has decided to retire his course after 17 years (wow!)
While I’m still new to Toki Pona, and know little about the language’s history, I know jan Pije is an important figure of the community and that his “o kama sona e toki pona!” course is a classic, though apparently a bit controversial when compared to the official book. It seems there was some kind of strange competition between his way of speaking Toki Pona and Sonja’s Lang way. I don’t know the details, nor what to think about some probably decade-old conlang drama, but it still feels a bit… sad?
Did you use his lessons? I’d be curious to hear about your experience. For people looking for an alternative, jan Letan’s lessons seem to be great. I’ve started to study them in parallel with the Pu and they complement it pretty well so far.