I know there’s truth behind that, but in my tests between the two, I didn’t experience enough of a difference in practice to outweigh the quality and compactness of the B158. I don’t have the tools to do lux readings, but the beamshots seemed at least comparable to me. Perhaps there’s more to an aspheric than raw diameter?
Edit: and mod thread here. KKW mentions getting 310K lux from a dd XP-G2 S4 2B.