I am using it . Its battery is amazing . RAM is bit slow . Its internal memory is 11.5 GB( memory limit for apps) . Back camera is just amazing. Front is not bad but not so good as well.
If u have any questions about it, please ask me iPad 3 is fine only on some games(It’s fine playing my favorite games), a bit lag sometimes but not much with iOS 9.2 and above. Still on good speed on 3G but I reckon should use this if you’re okay having wifi.