It's all a matter of opinion. Some folks think you have to have a .338 Lapua to kill Elk at long range, some think .300 WinMag is the best caliber every invented. Everyone has their favorites...But the fact still remains that there were guys making 900+ yard kill-shots 40-50 years ago with a 7mm RemMag elk hunting.
The 7mm STW is also a very solid competitor for that category, as it was designed for long range medium-to-large game hunting. Not to mention with today's technology for bullets there are 180-190gr bullets available for the 7mm's that have higher BC's than alot of the stuff out there available. Also the STW is better on barrel life than the 7RUM. Not by much, but 500-750 rounds. Might not sound alot, but when you measure in 1,000-1,500 vs 1,500-2,250 shots, it adds up.
I have been thinking about getting a 7RUM that my local store has for really cheap, just so I can rebarrel it to another 7mm STW.
These are simply my opinions...Everyone has a different one.