LW,
I have now fired several more .41 Silvertips into (temporarily) live deer and even an armadillo.
Penetration was not excessive. In fact, a shot fired into a doe weighing just over 100 lbs, entering just behind the shoulder blade from about her 4:00, did not penetrate the skin on the far side. It DID level her decisively- she had been hit in the spine with a hunting rifle, and had been trying to run on her forelegs. This is with a 3" bl 657 from about 15 feet. With most hollowpoint ammo, shorter barrels mean less expansion, and thus, more penetration. If you are using a longer barrel, you could expect less penetration.
On the whole, Silvertips in general have a good reputation, with the caveat that sometime folks complain of too little penetration. It is interesting that you mention the Silvertip's stats as being excessive for SD use- Magsafe typically loads very light loads at almost rifle velocities. I respectfully submit you might want to test a Silvertip into a row of water-filled gallon milk jugs before you make that decision.
Best,
John