Pros/Cons of jailbreaking my iphone 4s?

I have the latest version of iOS 6, I've never jailbroken anything before. I've read how to do it, but I'm still kinda scared that something will go wrong and I'll have to get a new phone. I read somewhere that I should restore it before jailbreaking it? I really don't want to do that. Will jailbreaking it erase my pictures/texts? Is the stuff on Cydia free?

Virgin mobile iPhone 4S opinion?

I know everything about all the prices and plans for all the iPhones on all the carriers. I'm set on getting an iPhone through virgin mobile. But should I get the four or the four s? The only difference it would make for me is the storage 8 vs 16. I could easily use 16 but 8 will also work. 100 dollar difference is a lot for 8 extra gigs of storage and I don't know if it's worth it. Opinions? IPhone 4 vs 4s? Any other information and opinions about the phones overall is welcome too, as well as problems unique to virgin mobile services.

What does a cracked digitizer mean?

I just bought an iPhone on eBay and the seller keeps saying it's fully functional with a cracked digitizer. As I recall, a cracked digitizer means the phone doesn't respond to touch, right? So, how can it be fully functional? Does this mean when I receive the phone and power it on it will be covered with those white spots? I keep asking for a picture to see where the white spots are and asking what the impact of a cracked digitizer is but he's not responding to my messages. Should I be concerned?

How to create separate iCloud accounts with one apple ID?

In my family we have an iPad and 3 iPhones. However, all devices are using the same iCloud account so only 1 phone is fully backed up. How do we create separate iCloud accounts but keep the same apple ID?

Thanks in advance

Added (1). Is this possible in a way that we can share purchases?

Iphone tracker software for computers?

Hi. I lost my iphone yesterday and i wanted to know if there are any free softwares where you could track your iphone. I need this without downloading the app on my phone first.

IPhone was stolen and it says it is offline?

My iPhone was stolen yesterday at football. *They stole $20 too /:* Anyway, I got on Find My iPhone and my device says "Offline" and will not give me a location to find it. Is there some way I can turn it on?

Does a jailbreak use 3G data when not in use?

My iPhone is Jailbroken on iOS 6.1 and I usually leave 3G data on all the time but with the new jailbreak I think it uses more data when I'm not even using my phone. I do not have an unlimited data plan so I need to watch how much data I use. Did anyone else have a problem like this too or is that normal?