As far as I'm concerned CityLink were only useless once - when they failed to allow me to speak to a member of staff or give them an alternative address. As soon as I'd realised City Link weren't useful to me as a courier and contacted Overclockers about the problem and Overclockers promised to switch courier, it becam their problem entirely.

Thanks for the recommendations - I'll bear them in mind! I still need to buy a damn soundcard... ;)