I don't know if my battery meter indicates the correct battery level, but at least it's very consistent. I did test how long it runs without completely powering down for 4 weeks, and I had to recharge it every Sunday. Now I'm going with completely shut off for the night, and so far in my 1st week of doing so have about 11 days. Only thing about that what I don't like is, that I have to wait until the book "booted" when I turn it on. So I guess I prefer charging every week instead of having to boot.
About PDF engine, I think I'm pretty ok with it. I would just prefer if authors/distributors would care a little more about "column-flow" (sorry, I don't know the proper term). Sometimes I read a column at the beginning, and then all of a sudden I'm at the end of an article and after that I find the rest. So I rather use the zoom and pan option instead of the font size increase (which I would like, too).