Kbin is tolerable in a mobile browser, but it actually becomes quite good once you decide to use Firefox on mobile and install the Tampermonkey addon along with some community userscripts to improve the functionality. Kbin is much younger than Lemmy, so it’s just playing catch-up right now.
On PC, I very much prefer Kbin’s user interface (but still with custom userscripts and a few minor changes to the theme I use).
My biggest problem has been that the ink always dries up, since I don’t print very often, and a laser printer has solved that for me. Now, about 3 years later, the black toner is still at 90%, and still working reliably.