Yeah it's amazing how incredible Calibre is at organising books but terrible it is at displaying them.

As a matter of fact though, I think I have found a very good epub reader which I don't see mentioned very much called Cover.

It is ridiculously smooth at displaying epubs, maybe even more so than edge. I was reading an epub with tons of images and I could swipe left and right between pages multiple times without waiting a second for reflow, almost felt like swiping a pdf. Whereas on all those other apps the book was blurred and did not scale how I would expect it to, to fill the screen. On cover everything is displayed how I think it should be displayed without changing anything. So yeah, cover A+

https://www.microsoft.com/en-us/p/cover-comic-reader/9wzdncr...