Claud Butler's Roubaix (£400) is a 16-speed Sora equipped aluminium racer that last year swapped its steel fork for carbon. It hasn't really changed for 2006, although for an extra £40 you can now get a triple-chainset version of the same bike.
The Butler has a frame with a sharply ovalised down tube and a top tube that's distinctively square-profiled at the seat tube. This medium size is called a 56cm, since Claud Butler measure to a virtual top tube. While no taller than the 54cm bikes, the effective top tube is a couple of centimetres longer - a stretch for me. There are mudguard eyelets at the rear but not on the fork. However, with only about 10mm of air between tyres and brake calipers, clearance is too tight for anything other than Race Blades.
The Claud has an integrated headset. Initially there was some play and brake-judder from this, and until I refitted the stem and top cap I was about to launch into a tirade against integrated headsets in general. I'll temper that to caution instead.
The Claud Butler is notable in that it uses almost the whole Sora groupset: hubs, front and rear mechs, even the chainset - everything except the brakes, which are Tektro. Since it's a 16- speed bike, it gets a short-cage rear mech. But this wasn't noticeably crisper than the long-cage mechs of the other bikes.
As a whole, though, the gears are the best here for racing, not because there's no 30T inner chainring, but because the cassette is a 12-23T. Instead of a 25T big sprocket, there's a 14T slotted in at the top end. This bridges the big gap between the 13 and 15T sprockets that even a novice time-triallist would notice. The flipside of having a closer ratio cassette, especially combined with the double chainset, is the lack of climbing gears. A bottom gear of 45in is something you'll feel on a 1 in 6 hill. We'd recommend spending another £40 for the triple option.