I really like RCBS Rockchucker presses and the new version is even better for these longer rounds. It is running around $125 or so from what I am seeing in the gun shops and catalogs.
Redding also makes their Ultra press which in my mind is the best single stage press on the market but it is much more expensive then the RCBS press but worth every penny.
Either press will perform well for you.
As far as dies go, I much prefer Redding dies over all others on the market for producing high quality ammo. They seem to induce less neck and bullet run out in loaded ammo then the other brands of conventional dies.
They cost a little more but I would highly recommend them. Remember, dies are a one time purchase if youtake care of them. Spend a little more and get a better die, you will not be sorry I promise you.
As a gunsmith, I look at all factory rifles as parts guns, but to be honest, the Rem Senderos are generally very good performers with taylored ammo to the rifle. If you want top performance in a factory platform, this would be a good selection in my opinion.
A properly fitted muzzle brake
should not effect group size in amy way. They can effect point of impact but not group size. So if youalways shoot with the brake on the rifle you will never see any difference.
If you use the brake on the test range and take it off for hunting, I highly recommend you zero your rifle without the brake prior to hunting, there can be a difference.
As long as you use a thread on brake, I much prefer the Holland QD brake for a hunting rifle, you will not loose any velocity at all.
If you choose to let someone port your barrel which in my min dis the poorest form of recoil reduction ever invented, then you will loose velocity.
If you get a brake have an externally threaded brake installed by a smith that does alot of them.
The Holland QD brake turned my 8.5 lb 300 RUM into what feels like a 270 in recoil, very impressive.