If you can top up a bit, try getting the 2013 version. Last longer on charge and don't have the slowdown issues the 2012's have.

As for the slowdowns on 2012's version, try clearing cache and dalvik. That would fix it for a while before it starts crawling again. Its torture if you're using the table while the playstore update apps in the background when that happens. If you're familiar with rooting and stuff, try using F2FS format. I did on mine, and the slowdowns goes away.

It's still a very good tablet. Not sure about gaming since I only play COC, but for everything else it does the job well enough even now.
Mine can't goncang too hard. Else the tablet will turn itself off and I have to open the back cover, unplug some of the wires inside and plug in them back in. After that try to turn it back on and pray, if it works that it would stay that way while I attach back the back cover. It's really a pain. Speaker is gone..no sound. Any idea how much to fix the speakers if I send to Asus?