ipad 3 with a5x or ipad 4 with a6x?

So I'm thinking of buying an ipad but I'm not sure which one is right for me. I do tend to spend most of my day watching videos,playinf 3d games and etc. I don't need a very fast chip that can load my game in 5 sec but also not too slow. Charging doesn't really bother me at because i usaully have to plug-in my device most of the time. Is the a6x faster when charging? I moslty use my tablet to surf the web and play games such as gamelofts ''modern combat 3/4'' and also 5 when it comes out. I dont wan't a too fast experience but again not to slow. Most people say there isn't much of a difference but when gaming is there? Can both chips handle 2 programs running at the same time while delivering the same smooth gameplay when playing a game and what I mean is let's say I want to listen to some music and as well as play a 3d intense game. I don't think the a6x is twice as fast but just slighlty faster but not by much but I need some pros and cons to know which one i should pick.