dawei - 'halitosis close' is a term I haven't heard in a long time, but it is a very accurate term at that. And at that range, sights aren't necessary. For carry purposes I would definately go with the S&W. For general shooting or field holster carry I would go with the Ruger -as said, they are tanks.
The heaviest thing to my S&W Airweight Bodyguard is the ammo - it adds about 2.5 ounces to the overall package, but I feel so much better with that little bit of added weight................ and of course, if you have to use the piece it gets lighter with every shot. Like I used to tell my troops - take a triple load, it will get lighter after the first firefight. Mikey.