WHat happens when you reload the 308Express? Can you get anywhere near the same velocity from a reload as Hornady is from there factory loads? If all this is is a 30/30 with different powder in it I don't see it as a big deal.
So far as I've read. No one has even been remotely close to performance of the Hornady 308 ammunition for hand loading. Now this is not to say at some point they won't get there. This even with closer in range where the pointy tip issue is not at play. I believe even muzzel velocity so far no one has been able to match.
So at this point I believe you have to juice up a 30-30AI to even get close to the new 308MX at this point.
So at this point the 308MX is higher numbers and flatter shooting. But this doesn't necessarily mean it is "better performing than a 30-30". Depending upon what performance you need.
If you hunt and do not exceed 200 yard shots. Then the 30-30 with the new LE ammo especially in the 24" barrel will probably fufill your "needs".
Just IMHO