I agree with the advice to just ride, to start with, and not think about it too much. But I've got to agree with the modern-bike crowd. My old mountain bike (1993 Bridgesone MB-4) fits me rather than way that Cannondale fits you now. I rode it as my only bike for 13 years and I had no problem with the John Tomac 'Superman' riding position when I was younger but I've been over that for a long time. You could make the Cannondale fit better but you'll still be happier and more comfortable on something modern that you can pick up used for ca. $1600. If you're not comfortable for hours at a time, you're just not going to be happy on that event.
A couple of years ago I finally got religion on modern road bikes when I rode my friend's modern Focus CX bike for a week, including up and down Glendora. When I make the budget for it, I'm selling something to offset the cost and buying something modern with hydro discs and etc. etc. It was marvelous being able to descend confidently (I'm not a natural), enjoying the cush of 32mm tubeless at 35psi, and one-finger braking. I love my road bike (a Vendetta) and it's such a joy to ride I can't get rid of it, but when I take it to big hills descents aren't the most fun because the brakes aren't good enough. Picture for shameless attention.
