Martinf: I was interested in your comment about there not being much difference between a sport tour and a mercury other than wheel size. I'm inclined to agree with you but I'd be really interested to hear from anyone who has ridden both. Not least because a mercury is currently n+1 and I already have a sport tour!
It won't be me, I don't have a Mercury.
I started building up my Sport Tour last weekend, its now about 80% complete. I'm in no hurry, but I will probably have more time to work on it as the days grow shorter.
When it is finished I will probably ride it over one of my regular circuits to compare it with my old 531-frame derailleur-equipped lightweight tourer. The latter is pretty close to an Audax bike, main difference is the slightly greater clearances and more relaxed fork angle.