Also would like to know how good battery life is for your player, either on audio or video.
So far, battery life has been impressive. I have watched two 720p shows back to back for almost two hours with the battery indicating that it is still full. I wasn't sure if this was accurate so I switched it off and then back on again and played with it for another 15-20 mins. Battery is still indicating that it is full.
PDF performance is mediocre. I have tested 6 different PDF's of different sizes. Two were comic books of around 10MB, these both failed with the error "Sorry! Can't Render Page!" .I tried a 50MB manual which caused the device to crash and reboot. The only one that worked was a 'CSS for Dummies' ebook. When you get it to work, navigation is reasonable but the lack of responsiveness makes 'turning pages' frustrating.
What I feel really lets this device down is its screen. At some angles the image quality is brilliant - but this requres quite a bit of effort in the first place, making sure the angle is correct to achieve an optimum picture. While this can be the case to some degree with lots of LCD's, the V8000HDY has a very small window where decent picture quality can be achieved. So far I have found that laying it on a flat surface produces the best picture with the least variation. Holding it in your hand at an angle is frustrating because you find yourself constantly adjusting the angle to achieve a decent image.
Another frustrating issue that other Ainol users have expressed is the inability to turn off subtitles in MKV's. I don't mean change them - I want to switch them off completely. There is no option whatsoever for this in the settings menu or while playing back the video. What a major oversight. I have tried to overcome this by removing subtitles using MKVToolnix which successfully remuxes the file, which plays fine on my PC, but crashes the V8000HDY, forcing you to hard reset the device.