IPhone 4 or iPod touch 5th gen?

I have an iphone 4 and i was wondering if the ipod touch 5th gen would be better. I know it has dual core and is much much thinner but i don't know if it's much faster. I also don't know if the RAM is upgraded in the ipod touch. Any suggestions?

Should I stay with the phone I have or get iPhone 5?

I have a wild fire s and it's really small for and android. And it's fat and it's slow
And ontop of that, I have metro pcs for service. It's terrible, I'll send a text and it won't really send until the next day or some one will text me and I'll get it 1 Maby 2 days later. Should I stay with this phone until iPhone 6 or get the iPhone 5 now. Or any other phone recommendations if so, pricess?

Is it worth upgrading my iPhone 4 to an iPhone 5?

Pearsonally I'm stuck with a decision because I've had my iPhone for 23 months now and pearsonally when the iPhone 5 was announced I didn't really want to upgrade because it had no NFC and then I thought if I got it sim free it would be better so should I upgrade or wait to see what apple has to offer next year? Thanks for answering!

Added (1). Also another reason why I wanted to upgrade is because I might getting it sim free- that means I can get 4G with the new EE 4G network also the reason why I didn't want to get it is because it supports nano-sim which I don't really like the idea of so should I upgrade or not?

Can i trust buying an iphone off of craigslist?

I talked to my phone company and they told me that I'm not eligable for an update for like a year and a half. They did happen to mention (because i want the iPhone) that if I got one from a friend or family member or off of a website I could swap phones basically with no extra charge. I want an iPhone so badly and I might be able to get my aunts old one (because she is getting the 5) but if that doesn't work out, would you trust buying an iPhone off of craigslist?