Battery life is average for a tablet of this size; that is, it's limited and a great argument for the 'old' E-Ink displays.
Though the manufacturer quotes 10 hours of reading or video, we managed around six hours of mixed use, with the device losing around a fifth of its battery even on days when it wasn't used at all.
Perhaps most irritatingly of all, when it's run-down 70% of its battery an LED light starts flashing, which isn't appropriate for a device likely to be used to read books and hence left in sleeping areas. In a dark room it's infuriatingly bright.
We ran the Nyan cat test video for 90 minutes and found that the fully-charged Arc at full screen brightness dropped to 82% battery level, which is about the same as the Kindle Fire HD.
Sound quality, meanwhile, is pretty poor despite emanating from front-facing speakers; it's flat and lifeless, but OK for using on a desk.
Through headphones sound quality is acceptable, though lacks mid-range aid a treble-heavy vocal.
And now the benchmark tests: the AnTuTu app test produced an average score of 11,230 for the Arc (4.5/5 stars, and well above average for a tablet).