My only advice, based on contemplating this same idea on a different platform, is to sell it and get what you want.
I had a project shift course in the middle. I followed through not being 100% sold on the chambering, etc. Now, I'm sorry I did. I can unload it, but I'll likely lose a good bit, so it sits in the safe.
I would wait and get exactly what you want. As you can see from the few that are selling their CLR/NULA/Hybrids, you will take a bath if you unload it. You will also likely sit on it a while.
I'm not knocking Melvin's work. I'm just commenting on your second guessing the current chambering as well as a magnum in general. You likely won't be happy with anything you send up with on the current donor.
