I've also been looking at getting a Dawes Horizon - my limited budget puts the Galaxy just about out of range so I need something to tide me over for a couple of years until I can afford something better.
As someone already pointed out, the Horizon is built with Reynolds 520 tubing. I can't find any information about this stuff on the Reynolds website. Do they actually make the stuff themselves or is it some cheap foreign version with Reynolds branding? Even if Reynolds had information on their site, the technical specs wouldn't mean much to me anyway. So can someone tell me what are the practical differences between 520 and 531 tubing? My current (ancient) bike is 531 so that's what I'm used to - will I notice the difference?
Also, I'm looking at a special offer for last year's model on the internet but as I have never bought a compact frame before and have never used STIs, I'm a bit concerned about buying without trying. (My LBS is a Dawes dealer but they only keep mountain bikes in stock, not tourers, which doesn't help.)
So, what size frame should I go for? For a standard frame I'd go for a 50 (c-c) or 52 (c-t) - even if someone could tell me whether Dawes measured c-c or c-t would be a help cos I'm guessing it's either the small (43) or medium (46) that I want.
And are STIs difficult to use/get used to? Will I need help/instruction first time I use them?
Sorry for so many questions - any answers would be much appreciated.