Not sure why, but I feel a need to pick on the "big" carbs. From the results the AFR at WOT was pretty good on the big carbs, so there may not be much more power there. All of the tuning would be to get some measure of street manners. The "little" Demon didn't put up the numbers but I look at this way:
654HP
10+ with the added timing (conservative)
5+ with a flatter fuel curve (conservative)
2+ with the bigger spacer (complete guess)
=====
671HP
And it already has some decent manners. I know you go for every last bit, but are you going to even notice the difference of 10HP on a 700HP motor?!!!

For me, the Demon is the clear winner, and the best choice to spend time fine tuning.