I think you answered your own question, stevebax - if you want it to shift "perfectly" stay with a Campag-Campag combo - mind you, I doubt front shift is perfect with Q rings - in fact it's almost impossible that it would be, Q-rings by definition operate a long way out of the design envelope of the FD ... it was never designed to have the relative height of the chain and the shift plates changing by the height of the teeth plus *plus* any significant eccentricity in the rings during the shift.
95% of the FD failures that we see in FDs that are not attributable to poor set-up or that are not genuine warranty are with Q-rings or with Osymetric (worse ...) because of the way the front shift loads the FD cage outside of it's designed parameters. We also see lever failures, too as riders have to hold the LH shift lever over aggressively to get the shift to happen - again Osymetrics cause more issues than Q rings but they are still in that mix
Chorus and SR, Bikejulio - overall on the cassette / chain, you should so no real difference in durability, if anything the Ti sprockets are slightly harder-wearing than their steel equivalents but they can take a slightly greater toll on the chain. It depends quite a lot on how the cassette is used (environmental factors, shifting pattern, etc).
Velotech Cycling Ltd (UK Campagnonlo Main SC)