I have both (even have both barrels for the P229), prefer the DW.
For me, SIGs have a very high bore axis while DW (M1911s) shoot where you point. Also, the trigger is MUCH better on the DW. While I like my P229, I do not like the long DA trigger pull.
Doesn't matter what caliber you choose, effectiveness is a dependant on where the shooter places the bullets.