Versatility and Value

I am considering a future upgrade later on down the line between the 5D Mark II and the 60D. To give some perspective, I have a fond love of my EOS Elan II e in 35mm and for digital... I own a 10D and a XTi. I have read that regarding sensor size goes... A full-frame sensor is essentially the same size as 35mm versus the APS-C sensor which I have become familiar with on my 10D and XTi. That's the one thing that has me interested in the 5D Mark II. However... I am primarily an enthusiast photographer and on a bit of a limited budget. The 60D is in consideration because the value of the camera is good, but it's constrained to the APS-C sensor size.

I mainly own full frame EF mount lenses and personally don't see any reason to buy EF-S mount lenses. I just don't know if it's better for me to just save for the quicker goal (60D) or if it would be better to take a little more time to save up for a tool with much more firepower (5D Mark II).