I think nearly everyone would agree that custom dies for a specific rifles chamber will inevitably help anyone make better ammo.
Certainly it's been proven time and time again that the spectrum of reloading methodolgies can obtain great results though.
Nathan's point on the double radiused shoulders being tough to replicate for the die maker is a valid one. Just my opinion...but that is likely not to be the constraint for most folks attempting to squeeze the last bit of accuracy from the gun/ammo/shooter "system".
Plus it's a Wby...that makes it awesome without even shooting it
BTW-LRH if full of good folks. Here's a civil discussion even after my "sharp" reply above:(
Thanks for sharing that perspective Nathan. It will only serve to help the original poster make a good decision now that he knows the why
behind your post.