Very nice. Ultegra/Tricolor is my second-favorite group, although I prefer the later 8-speed components with dual pivot brake calipers, paired with a compact (for old men) crankset.
Also really like the non-aero Euro-centric brake levers.
Got a couple 640X groups in excellent condition stashed away for potential future builds, including hubs and wheelsets.
Here, on the Bob Jackson: