A couple of questions. Do you reload? Is giving up your 1911 going to leave a smoking hole in your pistols?
Factory ammunition for 270WSM is going to be costly and/or hard to find. Not an issue if you reload.
If you do reload, there are more bullets becoming available in .277. I reload for a couple of magnums, 340WBY, 300WBY, along with 6.5/284, 223REM, 44mag, 357/38SPL.
I have noticed that WSM ammo is as expensive as the WBY factory ammo recently.
I like the idea of the WSM/RSAUM's. A beltless medium capacity magnum cartridge, of superior efficiency, to the full length belted and Ultramag cartridges.
I have nothing bad to say about the A-Bolts, my brother had one in 7mag and was pleased with the fit and finish, and classic appearance of the Browning rifles.
If I had all the pistols I want/need, I might seriously consider this trade, simply because I think that I might enjoy tinkering with something a little different. I might not choose 270 though. I have no 7mm in my rifle rack right now, so. Enjoy!