There aren't a whole lot of weapons who's scaling changes drastically as you upgrade them are there? Does the scaling change at all? I know that in some weapons a C scaling can work out to be more than on another weapon's C scaling. At least, that's the impression I got - does this mean that the param bonus actually does go up marginally, and the only reason that most of them don't hop from D to C or C to B is because the scaling doesn't change enough?