Before you buy check out B & H photo an also amazon.com to find a good price. I bought my canon t2i from b&h and couldn't be happier with how much I paid and what I got.
best thing to do is go put them in your hand, and see how they function i shoot with nikon for a living and hate how canon's are set up and how they feel in my hand, canon shooters feel the same way about nikon, you need to play with them.