at some point, it is how many angels can dance on the head of a pin. 9310 is a standard. Carpenter 158 is proprietary alloy, and no real difference from 9310 in effective use of weaponry in a bolt. The difference between C-158 and 9310, I just don't see it. There is no evidence, let alone testing differences to the practical extent that it matters. How many times do you hear of a broken 9310 bolt machined by a reputable company? This is a stupid argument, and one that has been debated over and over again. 9310 and C-158 are very, very good and very similar. One has more Molybdenum, the other more Chromium. One is harder, the other is marketed more. S-7 is out there, and whatever the rumor mills are probably the best bolts in the business to-date: LMT and KAC.
Now, 158+. Sounds like Carpenter has sold some magic snake oil. Maybe, maybe not.
Nitriding, QPQ and DLC, NiB and Chrome finishing also need to be considered.
This is not a dig at Geissele. Not at all. Big-G is one of a few brands that I trust will get the materials and the coatings working well. I just think, to some degree, we can focus on the technical aspects of things that aren't broken.