My Son Rick and I both hunt with rifles chambered in 6.5-284. Pronghorns, big Mule Deer and Elk are no problem with this cartridge. I built Rick's on a 700 action with an X-Caliber 7.5 twist barrel in an MDT chassis and mine's a pretty-much stock Savage 110 with an 8 twist. Both shoot very well and I've found them easy to develop loads for. This is definitely a handloader's cartridge. I don't believe I've ever seen a box of factory ammo.
I still have some 140 A-Max's for my rifle, but of course those have been discontinued. My Son has cleanly killed three nice Elk with his, including an incredible one-shot "bang flop" at 702 yards this year. We don't prefer to shoot game that far, but there were a bunch of Elk in a giant bowl with no practical way to sneak closer. We'd been practicing a lot, out to 1,200 last Summer and this Spring, and 702 was a very comfortable shot for him. He's pushing the 147 ELD-M just a smidge under 3,000 fps using RL-16. I thought RL-16 might be too fast, as I use H4831SC in my rifle, but it drives tacks and gives great velocities in his gun without excessive pressure.
As others have said, the cartridge is light recoiling, especially through a suppressor, and retains its accuracy, velocity and energy for clean decisive kills. Rick also carries a magazine full of with 155-grain Lapua Megas for shots under 200, as we're not confident the ELD-M would perform as well up close. We've been amazed at the great terminal performance of the old A-Max and the ELD-M past 200 yards. With the heavily-constructed Lapua bullet (2850 fps using H1000) point of impact is very close to the ELD-M's zero at 200, so he never needs to mess with his scope settings.
There are LOTS of good caliber choices out there but we've not found any better for the western hunting we do. Best of luck to you Sir!