I shoot my Big Five with 9.3x74R barrels a fair bit. The 9.3 barrel set is much lighter than the 470NE one so the balance changes but I don't find it to be an issue. The weight shifts towards the back and it stays between the hands so the gun is not out of balance. The upside is the recoil is quite mild due to relatively heavy gun. In fact Krieghoff produces their double in a lighter alloy version up to 9.3 or 375 calibre (not sure which one). Personally I think my 470 and 9.3 is a great combo, like I said I use it a fair bit with both barrel sets and think it is a great rifle and one I can definitely recommend. The 9.3 barrel set is not soldered and is user adjustable for regulation which is quite handy. I've attached pictures of the two barrel sets, not sure how well it shows in the picture but one is a fair bit thinner.
