You can put pretty much anything you want on it that is a road groupset today. I upgraded my old Raleigh Comp GS and a Schwinn Paramount frame. Doing all the work myself and waiting for deals on the components I saved maybe 500 to 1000 dollars of what a new bike would have been with the same components. However the new bike would have been 3 to 5 pounds lighter.

If you ride the road a lot and ride far and in rolling terrain, you'll appreciate a lighter bike. I finally got one this year, though I did thoroughly enjoy building up and riding the Raleigh and Schwinn for many years. But the new bike is more enjoyable, mainly because it's lighter. The Raleigh built out at about 23 pounds and the Schwinn 22 pounds. My Tarmac is 17.8 pounds.

So if you can put your newer Dura-Ace on it and not have to spend much more getting the other stuff to work with it, you'll be off to a good start. Ride it till you get the enjoyment out of it and then treat yourself to something new.