Kelly honestly you could go with any of the three. Long throat a 7 RM I think you'll get there. Plus /minus 3100 with a 160 should not be hard with todays powders.
The 7mm Weatherby is a slam dunk (I guess, never owned one). But reliable people on here get over 3100 routinely.
I'm happy with the Mashburn (which started out as something of an experiment) and like it a lot but the wildcat status and forming cases is a turn off for lots of people. Others are not bothered by it at all.
I bought the Quality Cartridge stuff but people on here gave me subtle hints about how good it was. I have not tried it so can't comment.
If head stamped brass is a concern, go Weatherby,7 RM etc etc.. But I know friends of mine hunting with Mashburns have taken rifles and cartridges into Mexico and Canada.I have not flown with mine yet, but am not really worried. Pay your money and pick your poison.
You could make life real simple and just get a 28 Nosler!
