The S&B I have shot at night (72 round night IDPA match) had the
LEAST muzzle flash of any factory load at the range that night.
Extremely low signature.
As far as fouling, it is probably a bit dirtier, but ANY tactical 1911 should last 500-1000 rounds between cleaning of even the dirtiest ammo.
For my money, I LOVE the S&B, and I have tried everything else (Fiocchi, PMP, PMC, Fed., Win, Rem...yadda yadda yadda)