Absolutely. Most books I read would be significantly worse to read without that static layout, pretty much every paper, every programming book, every science book, etc. I want books that are explicitly designed by somebody who gives a crap for a certain page size, not some automatic algorithm that gives me something that maybe fits the screen but loses all the context around the few lines I'm reading.

I can't remember a single non-fiction epub that was better than or even equal to the PDF.