As a believer in Sigs, I known I prefer the Sig from years of carry. S&W may take a bum rap for this contract.
S&W's third generation autoloaders have come a long way and their TSW line can go toe to toe with SIG. As a matter of fact, since they have a manual safety and SIGs do not, the S&W's might be an even better choice for uniform carry than SIGs.
I read several stories about bad guys getting a cop's gun away and pulling the trigger and nothing happening because the safety was engaged. If they would have been armed with SIGs, they would have been shot but because the S&W's have a manual safety, before they had a chance to figure out how to disengage the safety, the LEO was either able to regain control of his gun or shoot the badguy with a back-up gun.
Yeah, I know. With properly weapons retention, this should never happen but apparently it does and the manual safety on the S&W's can apparently make a big diffference. Now if we're talking about guns issued to either detectives or desk bound admiistrators who are required by regulations to be armed but rarely have a reason to discharge a weapon in the line of duty, I would pick SIGs DAK line -- 229s for the detectives and 239s for the desk bound admiistrators ... both in .40S&W.
The SIG DAKs have a repeat striker capability which is lacking on S&W's DAO models ... both companies have something to offer to the LEO community.