I don’t see a problem with the OE Magnum rockers. The aftermarket should (key word there) have rockers that are dead on accurate in there ratio. A problem that the LA rockers have, it being a 1.5 but normally less. IDK about the Magnum rockers.
If the Magnum rockers are not flexing and are true in there ratio, then there is no gain.
For your goals, I think you’ll be fine.
