Way better (resale) existing value over time if it has original paint. You'll not find a nice waterslide decal to match the originals and the investment cast lugs which are a nice feature ill look crummy with PC as they'll fill in a bit.
Heck, for the money you'd spend you can sell the vintage frame and buy a modern frame like Nashbar or scattante and call it a day. Nice and shiny and you'd have CF fork etc to go with the STI. Someone on the board is sure to snatch that frame up. It's too big for me or I'd make an offer.