Both the bikes you mentioned are nice. However, I second some the suggestions here for the Specialized Roubaix or the Cannondale Synapse. I have a carbon fiber Synapse... I absolutely love riding that bike. It has a little bit more relaxed frame than most race bikes but it's plenty responsive for me! You'll see both the Roubaix and Synapse frames being ridden on the pro tour where sections of the race course include some rough cobblestone. I figure, if it's good enough for the pro tour, it's good enough for me!

If it were me at 65 and I was buying a new bike, I would get the best that I could afford and that fit my riding style. An '89 cannondale lasted you 24 years... the next bike you buy may be the last one you ride - get it right!