The 7RM is an idiot proof case.
160-162g at 3100+ with extreme accuracy with Retumbo and Fed 215's
150-154g With max load of R#25, Win mag primer at 3200+ on a 26" barrel.
I also shot a std 280 Rem factory with max load of R#19 and 160g Sierra at a tad over 2900 fps, load right out of the Nosler manual for their 160g bullet.
You should be concerned about the range you are shooting and down range ballistics you will be needing for the distances you are shooing.
For a standard run of the mill bullet, the 162g SST is a Tough accurate bullet, I highly recommend it, and it will love to be touching or a slight jam on the lands for best accuracy.
If you want to compare a custom 280 to a custom 7 Mag(I have), then the 7RM will accurately shoot the the 162g A max at 3200 fps out of a 28" barrel with Retumbo and Fed 215's....that is STRONG!!!
Make it fun for you and Good luck