Would it be smart to get the iPhone 5C off contract, and get iPhone 6 next year?

Long, long, story short I'm stuck with a slow 8gb iPhone 4, and I have official ios 7 beta and my phone just got way slower, and no way I'm going back, since ios 7 is too useful and gorgeous. I would love the faster processor in the 5C and the 5in screen, but if its, lets say, $300 would it be worth it to get that this year and get the iphone 6 next year when my contract is up and I can get the 6 for $200?