I used to use the 60D before I switched to full frame. On top of what everyone said already I will add this, if possible then try and handhold both the bodies. See what feels comfortable in your hand. I still prefer the 60D's grip and its ergonomics as it fits my hand better than the 600/650D. Also, 60D and 6D's body, button layout and ergonomic is nearly identical and if you plan to step up to the full frame 6D in the future you will find it famliar.
Skip the 18-55 kit lens, and get the 40 EF lens. Remember any "EF" lens will work on both Canon's crop bodies (like the 60D, 650D) and full frame bodies (6D, 5D2, 5D3, etc). The" EF-S" lens (eg. 18-55 you mentioned) however will only work on your crop bodies.