I had one of the Panasonic models a long time ago, and I used to love typing with it.
I didn't have a reliable source for pen cartridges though, so I usually saved it for things that were "important" at the time.
Everything else was typed on an IBM Wheelwriter, which in my mind is still the pinnacle of typewriter technology.
Supposedly you can still order the film ribbon cartridges for them online.
Yeah, I had one when I was going to a community college in the 80's. I think I got it because it was actually less expensive than some other standard kind of electric typewriter.
Man, I wish I still had it now seeing all the plotter functionality that I was not taking advantage of…
I had a plotter that took these pens. I couldn't afford to buy new pens, so I sawed one in half and soldered a threaded insert in to make a cap, so I could refill it. Refilling worked, though wasn't as reliable as a new pen.