Should i buy my iphone 4S with or without a contract and why?

I'm going to buy one for christmas (and please don't say get an S3, my itunes library is loaded and i intend to make use of it. However i don't know whether to buy it sim-free or on contract. Contract appeals to me because il know i'm not "paying" directly for a call or text and paying each month sounds more agreeable. However if i somehow fall short on cash to pay each month that scares me. The sim free version appeals to me because i'm not tied to any carrier/commitment and if i travel around the world alot then its useful to just swap the cards in/out. On the other hand, like stated earlier i don't like the idea when i'm calling/texting i'm being charged, i like the post-paid option better it seems. Because on my existing ageing samsung galaxy S2, id lose credit randomly. Only found out last night it was dumb roaming -.- Anyways what do you guys think? Thank!

Buy without a contract and use on straight talk. They offer unlimited plans for 50.00 without a contract and use ATT's and Verizon's Satellites, so the service is just as good.

Hi. If you go with contract then you are tied down. You can get out of the contract if you pay an early termination fee which can be $300. If you go without contract like prepaid then you are just month to month if you want. You add in minutes & whatever you like whenever you want. You can leave any time if you want