Adam, sounds like your string choice is virtually identical to mine (for my modern bows), only using BCY's dyneema where I use Brownell's dyneema.
FWIW, I have found dyneema to be as much superior to fast flight as fast flight is to dacron... And I have found it to make some of my worst modern bows actually behave as if they were half way decent.
As far as durability, sometimes its tendency to "fuzz" up worries me; but I just wax it down, and replace it when the fuzz starts balling up. I have gotten a year of hard shooting out of these strings, and only replaced them as a precaution. So far, my strings have been pretty much bullet proof. Not broadhead proof, though... And on that occasion I only cut through half the strands, and the string held until I could unbrace the bow and replace the cut string with the spare I habitually keep taped to my riser.