Nice bike the BMC - hope to see pictures in due course, but I would go with dual front and back, you can never have too much braking capacity - remember it only needs to be a downhill bend, or a bit wet, and you could be very grateful

_________________
Wiliers: Cento Uno; Cento SLR; Imperiale, Zero 7 (all Super Record 11sp naturally)

I took the single pivot rear off mine (its 2007 chorus though) and replaced with dual pivot. I disliked the big difference in lever feel between front and rear with the single pivot in place.

There is a caliper spring tension adjustment bolt on the side of the single pivot caliper (just like on the dual pivot caliper) that allows you to dial in tension, which will directly effect "lever feel" you mention. EM3

_________________
________________

My 2011 Cervelo R5

Somebody mentioned the front/rear single pivot option. I made one of these, though it wasn't easy since the rear single pivot axle is special, you cannot just use a longer axle from another manufacturers single pivot brake (and the rear short axle will only work n some front forks with long bolt, and not in the majority of modern carbon designs). I ended up taking a old Modolo titanium axle, and had it machined to thread into the caliper body. It was installed on a customer's lightweigt "climbing bike" (BTW I never understood why would someone use a less efficient brake on a bike used for mountain riding - if you go up, usually you have to come down - even if it's a hill climb race!). Anyway, I tok it for a testride, it worked OK, I can imagine using it on a time trial machine for better aerodynamics, where braking performance is not so important.

I did. I think it would only save another 10 to 15 grams. I don't have a weight on each brake but I think the single double set is 15 lighter than the double double.

My choice is single pivot in the back. 90% of the stopping power is in the front brake. The rear is used for modulation and you do not want to have too easy a time locking the back wheel.

Re: single pivot front/rear
In case of the 2007 Record, according to my notes, 16 gr was saved by using rear single pivot in front, and another 17 gr by using lighter brake pads, drilled pad housing, titanium screws and aluminum axle nuts. It was a sub 250 gr set, pretty respectable weight, today it's easy to buy somithing like this off the shelf much cheaper than doing this conversion (even if you have a free rear single pivot caliper to convert!)