I would never trust halfords bike 'builds' (then again i would check any new bike over no matter what shop built it). I bought a Boardman Race team Carbon a few months ago, the brakes werent set up correctly, seat post was loose, bike computer hadnt been setup correctly and service was poor. Someone else I know that bought a bike from the same store about two weeks after me (through the B2W scheme) had a crank fall off on his first longish ride even after they had come out to setup his bike 'properly' after various issues. They admitted liability on the cranks and he got a new bike and compensation.
I know this isnt the case with all Halfords staff, I know someone who works in a bikehut and he is very good at repairs and has a good overall knowledge but unfortunately my experience with them has been poor.
To the OP, you shold be able to have a look at the Boardman in a local halfords if you have one.