From what I've seen, the stock cannondale is about as fast as a 450r with hrc kit and pipe. But we all know how those discussions go so lets skip right over it. I personally like the ergos of the 450r a little bit better. The 400ex peg to seat height is just too small for me.
But in that case, maybe the cdale should be the backup. It will rarely get used though.
If you don't mind me asking...where did you get the cannondale?
I found it in Goodlettsville, TN. It had been sitting for a while, since the valve cover corroded, but it was garaged. It is a speed. Maybe over the weekend I can snap some pics.
It was a nice place, thought about knocking on some doors to see if I could find me a sugar momma while we were there. With as new and nice a houses were there, I am sure they could fund my habits!!