Koodo is the way to go
However, more recently I have been using "Koodo" reader and library for both epub and pdf
It has a great visual library too. I only use Koodo now.
I'm really not confortable with projects that treat the Git history as junk, to the point I'd rather avoid that software. I daily use the e-reader Koreader, and sometimes Plato, and their source code and Git history are clear and documented (though I think Koreader's choice of Lua is poorly suited to the task). I could patch Koreader to my taste and send pull requests.
(This is not a flaw in the software, this is a flaw in me: I don't know how to read -- I'm assuming it's Mandarin Chinese, but I can't even reliably tell that.)
No.
Koodo is now what I use, it renders the best for me, I feel like I'm reading a paper book, which is great to me, the fonts and theme are great.
Calibre's epub reader is painfully slow to start, and it does not look that good either.
I wish other epub readers can have better fonts and color.