Same for me. I would say an electronic book has the advantage in searchability, but a well curated index might actually beat a naive text search most of the time.
On desktop, maybe, but I haven't used a decent enough reading software (like most web stuff, Amazon cloud reader is barely fit for purpose, and while I don't know what's "state of the art" in epub/PDF readers on desktop, the few I tried didn't facilitate reliable search and fast navigation either), and most technical e-books I keep as PDFs anyway, because the formatting almost always matters.
On e-book readers like Kindle, a profound disagreement. I can easily find what I'm looking for in a 1000 page book even without using an index in less time than it takes to type in a search query into Kindle's searchbox (especially since I switched from the old keyboard Kindle to touch-only Paperwhite). If there's a well-curated index at the end of the book, it's only that much better.
I think software could get somewhat closer to paper experience, but it needs to be faster. As long as random page access takes more than ~100 ms from selecting the page to full render (and in my experience, it's often close to 300-500 ms), you cannot really flip through an e-book the way you would through a paper book.
(Tangent: it's another of many cases where performance actually matters, because the difference between lighting fast and fast enough to tick boxes on your sprint plan is entire family of use cases.)
