I think the S2 is strong, and it has not really been around long enough to judge reliability. But generally Sig/Blaser products are reliable so I would not be too concerned about that.

I grew up shooting a SxS shotgun, and I do best with a double rifle that works the same way. That includes traditional safety, top lever, 2 triggers. I don't want a scope or a bunch of leaf sights that would just confuse me. Nor do I want the long-travel, somewhat hard to push safety/cocking piece of an S2 or on the Krieghoff. But that is just my personal opinion. Others do not mind it.