Random thoughts in no order...

The SR is smoother and fits in my hand much nicer. I felt that the shift quality is similar with the down shifts maybe a tad quicker with the SR. I actually think I prefer Shimanos upshift lever over the campy. I like moving the big lever over Campys smaller paddle but with that said the brakes on the Campy freaking rock and part of that may be due to there lever being pinned in one direction only. Again Smoothness is the biggest difference that I noticed but keep in mind I am also on a brand new wheel set with ceramic bearings as well as tubeless tires so it all plays in. I am not sure I would say SR is hugely nicer than the Dura Ace but it does feel more polished. Is SR worth $1,000 (estimating) more than 7900...... I don't think so but how do you put a value on any of this stuff. Is a $2,000 wheel twice as nice as a $1,000 dollar wheel.............
Installation as very straight forward once I figured out the cable routing. Campy instructions suck so for the most part you figure it out as you go along. The complete job from strip to rebuild was maybe a 4 hour affair in my garage. It was that easy.

Note: 7900 is not $1,000 cheaper than SR. It was merely a off the cuff figure. Maybe $500.00 is more accurate.