I'd go with Maguras or possibly V's - a bike like this will ask to be hammered and the solid feel of the rest will suit some nice solid brakes.
Speaking from experience canti's in the peaks are hard work... and magura's should retract a bit further from your rims than V's so less nasty graunchy noises when riding in wet gritty conditions. Pain to set up until you get the hang of them, but as long as you don't mind pulling the whole bracket apart and starting agin when you realise it's not at the optimum position....
Which maguras? (and most importantly what colour...)
Si F
That'd be a dream come true!
