I have followed this thread with great interest. I ended up purchasing a Campy Centaur crank from ebay (as someone else in this thread did) and figured I would give it a shot. During install, I noticed the BB had a pretty good grind to it so I pulled it out - the left hand side bearing was fully rusted after only 2 years of ownership (2 winters of commuting however). So I then ordered a Phil Wood 120mm BB and replaced both the BB and crank in one go. I added a BBG guard to keep the mudguard effect of the original.
With my measurements, I dont think chainline/q-factor/etc changed much at all - definitely within the accuracy of how I was measuring the before/after.
The crank I replaced was the 54T and the Campy came with a 53T and a 39T ring (a common combination) so I moved the 53T to the inner ring. There are 54T rings and larger available but they are a bit pricey (more than the crank/rings I bought off of ebay).
The increase in stiffness was very noticeable - especially when standing. The new crank arms are 172.5mm long and I dont think I can feel any difference in length.
Overall, a great upgrade with no downside - folding works as well as ever.
