One of the most attractive things about a surgeon is they are the only ones left that still do a factory remmy extractor. They were the holdouts. For a .308 bolt face action, id do standard without a moments hesitation. On a magnum though, a rivet style isn't field servicable, and the rivet adds a fail point. Stacking a m16 or sako type extractor on top of the right bolt lug never sat well with me. Just a screwy angle of ejection(personal experience). I wonder if surgeon adjusts the ejector position to accomodate for that? Like 5R rifling, m16 extractors are prevalent because people ask for them, not because they are superior. My opinion of course, but based on my own experience, and conversations with a few action makers.