Buying a new DSLR-- kit or just the body?

I have a Canon Rebel Xsi and I'd like to upgrade to a new camera. I've decided that I want a Canon 60D, but I don't know if I should get the kit lens with it or just the body. I already have 3 lenses (a kit lens [18-55mm], a macro [50mm], and a telephoto [55-250mm]). This kit lens is an 18-250mm, but it has the same f-stop as my other kit lens. Should I spend the extra couple hundred dollars to get the kit lens, or would it be logical to just purchase the body? I'm on a tight budget!