Stop being so OCD. It's a gun and you're going to shoot it soon enough and it'll be dirty AGAIN!
And for the record for most folks that is already super clean. Seriously. There's lots of us that would not even put in the time to get it to where it is in your first picture.
One thing to keep in mind that Flitz also removes metal. That's why it's used for polishing the outside of the guns by many to a mirror finish. It does this not by applying "shininess" but by removing metal until the whole surface is down to or below the worst of the surface scratches that give the S&W the brushed look. So clean the front face often enough to remove the last bit of black and over time you'll dull off the sharp edges of the chamber mouths.
I believe that I've read that the "Lead Away" cloths are also abrasive but on that one I may be mistaken.
Mag wheel polish and stainless polish are both also abrasive and will do the same thing as the Flitz.
Now and then isn't bad. But by the time you notice that the front face is shiny you'll have removed enough metal to matter.