I have a 16" grendel and an 11" ham'r. I've shot a few pigs with the grendel, and a couple pigs and a deer with the ham'r. Shot placement is key. (Duh)
I'm getting about 2500 fps with 123grn bullets in the grendel, and 2200 fps with 125 grn bullets in the ham'r. I think I could bet to 2300 fps with a different powder and a hotter load.
It has been fun to shoot the hamr, but I don't know that it's better. Forming brass is neat. Cutting down 223 cases and necking them up. But it's a lot of work. Of course, trimming was tricky. Lee doesn't make a trim for it. I had to get creative and use a 30 herrett gauge and file the primer pin down a bit. And I had to buy a harbor freight mini chop saw, and a jig........ So while brass is free, the effort into making a case causes me to hunt for my brass aggressively. Also, a sized 223 case still fire forms to final shape. The sides straighten out some and the shoulder sharpens. It's a little like fire forming a 257 Rob into an Ackley. But not quite as dramatic. You pick up about a grain of capacity.
And the Wilson barrel, while superb (sub moa 11" barrel? Yes please) was $250. My grendel barrel was like $150 I think. It's a ballistic advantage, and maybe a 1-1.5moa barrel. Grendel mags cost a couple bucks more. If you reload and like reloading and tinkering, the ham'r is fine. But it was designed to mimic the 30-30. It's not a long range caliber. The grendel is probably more versatile and easier to feed.
The 6.8, 6.5, ham'r, x39, 277 wolverine, they're all about the same. Pick something that makes you happy and roll with it. I honestly think they're all a little light for hunting. They will kill, but I'd rather have a little more oomph.
If all my stuff was stolen, I'd probably abandon both ham'r and grendel and find one of those small frame ar10's and chamber it in 6.5 creedmoor (or a 7mm-08 would be nice) Less recoil than 308, more power than grendel.
At least, those are my early morning thoughts.