Buying an iphone to use with straighttalk network

So I'm going to buy an iphone 4s and use a straighttalk unlimited plan. I'm not sure if it has to be gmsa or gms. Should it be originally from VeriZON OR ATT? I don't know much about it. Somebody please help before i go spend a bunch of money on a phone I can't use.

Can i get an iPhone with just unlimited texting?

I'm getting an iPhone 4s soon and i was wondering if i can get a plan with only unlimited texting (since i text more than i talk) I'm with telus, how much do you think that would cost. Just unlimited texting and a small amount of minutes?

Iphone stuck in recovery mode after updating to IOS 7 beta?

I tried updating my iPhone 4 to iOS 7 beta, without developers account, using restore + shift on itunes and clicking my downloaded IOS 7 firmware. This failed at a certain part, it said error 1934 or something, at that point my phone was still working, then I tried again and it became stuck in recovery mode. I tried different tutorials but I just can't get it working again, please help!

Why isn't the unlock process for my iPhone on iOS 7 working?

My iPhone 5 is an AT&T phone and I recently came to India for a vacation. Since I need my iPhone for work and everything, I decided to get it unlocked. My iPhone is on the iOS 7 beta but I'm not an developer. So when the guy who unlocked came back and we put the Airtel sim card in to activate it it said Activation failed, your iPhone is not registered, please register your iPhone on the Apple Developers portal. What do I do, I need to use my iPhone here in India very badly but its not letting me?

Added (1). Should I restore it back to iOS 6.1.4?

My iPhone 5 keeps saying no service?

Since yesterday my phone says no service but I'm able to use Internet when connected to Wi-Fi at home. When I ring someone the service comes back on but this only last for about a minute:/. I can't text anyone:/. Any ideas of what it could be?

IPhone 5 on O2 contract and 4g?

Will it work if I sign up today, the website says "no" and the phone isn't 4 g ready, but the guy in the shop says he will give me a 4 g SIM card for when its released, don't want to sign up for 2 years if not true, ty

IPhone 5 cases with raised edges?

Does anyone have links to iphone 5 cases which have raised edges that will help to protect it if it is dropped face down (I'm aware this won't provide full protection). Struggling to found any at the moment.
Thanks

Added (1). Sorry I forgot so say I want a reasonably slim one and not a flip one. I would like one that just covers the back, sides and has raised edges.