Everytime I see that ad, I get hungry.
The S&W and the Ruger are both tough as nails. The post that says that one is a tank and the other is a luxury car is just not my experience.
Both are like tanks. The S&W has a better action, in my opinion. The Ruger has no screws to work loose.
On the other hand, when the cross pin that holds in the rear sight decides to be contrary, there is no way to tighten it up.
And, in my experience, the 1970s gun writers who forever complained about S&W sideplate screws working loose were greatly exaggerating the issue.
In the first place, the screws are long enough that if they loosen (and it is exceedingly rare that they do), you notice it LONG before the screw backs out far enough to do anything. Just snug it back.
Secondly, you do not and should not EVER use loctite on the screws on an S&W revolver. It is just not necessary.
So, I view them both as good quality duty weapons. Neither are safe queens, and both are "fit for duty."
The only revolvers that are safe queens are Pythons and Korths (neither of which I own). I suppose a discontinued S&W for which parts are no longer available is also appropriate for putting away. That said, at the time the original owners bought their Registered Magnum or what we now consider a collector's item, they were bought as workhorses.
So, use them both and enjoy them while you can.
Your biggest factor is not wearing out either gun - it is affording the ammo!