Best Audax bike?

[redfalo]

For comfort and performance I'd recommend a Specialized Roubaix.

I'm also very happy with my Roubaix (a 2014 SL4 Elite).

As for the gearing, if you're a reasonably fit rider on a light-ish road bike and travel light, I don't think you need a triple. It can be a different story if you plan to do fully loaded tours in hilly terrain.

I am currently using the default setup on the Roubaix (50/34 in the front and 11-30 cassette at the rear), and did not run out of gear on PBP, despite 6 or so kg of luggage. As I intend to do Mille Pennines in 2016, I'll fit a 11-36 casette in the back, using Lindaret's Road Link http://www.lindarets.com/roadlink/

What 11-30 cassette do you use and with what groupset?

That road link is a great idea, not heard of it before. A nice option for longer, hillier rides.

Just doublechecked: it's a 12-30 cassette (not ann 11-30, sorry!)  on a 10-speed 105 mech. Bike was delivered with a Tiagra cassette, and I'm not on an Ultegra one.



 

[Somnolent]

I would definitely add my voice to the triple side for those of us who aren't mega-fit whippets.

And another.
Running 50/38/26 Stronglight rings on 105 5-arm cranks. 
Everything else is Campag 10 speed triple (12/30 cassette) for a gear range of 23" - 111" on 28mm tyres.
Works for me but YMMV