I use a ribble winter audax (sloping top tube model) as my main commuter bike.
The frame is very well made and has superb handling. Goes like it is on rails. It's very much a 'race' geometry and the rear triangle is too small to carry panniers.
Ribble cut corners on some things and not others. The wheels were badly machine built on my bike and didn't last long. I should have had them relaced by a good wheelbuilder. Some parts, such as the mudguards, are cheap. The rest is good - they tend to sell 'whole' groupsets (ie, if you buy 105, you get all 105 parts). I also found their after-sale support to be good.
I haven't kept a log of mileage on the Ribble, but reckon it must be around 15 000miles by now.