I agree with djb, though it's totally up to you as to how you want to build the bike. Looking forward to it regardless.

I just replaced the old blackburns on my bike with heavier Filzer aluminium racks and am pretty happy with the initial results. Mainly they have pannier stays that act to keep the bags out of the spokes which the others didn't. 32 and 42CAD for the pair at MEC.

I also have a Brooks C17 that I like but found a little too hard on my last trip and have replaced it on this bike with a Serfas Rx. 60CAD in Calgary. I'll post pics a little later on.