Originally Posted by tompe
No, they are not. Going forward 100 pages and then backward 100 pages will not get you back to the position you started with.
Even just reading as normal, the page numbers go out of wack...and that's without changing font sizes. I first read Mobipocket books on my PDA, and I was forever getting jacked up page numbers while reading. I might open a book and it says there are a total of 500 pages, then as I'm reading, I'd look down and be on page 600, and not be close to finished. I gave on on meaningful page numbers and just bookmarked.
It really wasn't that big a problem for me, since I tend to read books in big gulps anyway. The only time I found it frustrating was when I'd touch something and end up at the end of the book, or something like that, and couldn't easily find where I'd been.
The eBookwise is really my favorite reader when it comes to being able to recover my place when I jump somewhere I didn't mean to by mistake. That "BACK" option on the status bar saved me lots of frustration over the years.