I must defer to Mr. Allen, on sheer accuracy...the bolt every time. That being said the black rifles are certainly closing that gap at a rapid rate. I'm a fan of both, dependant upon what you're going to do and at what distances.
Now, you obviously have no intent of selling fur if the 300 SAUM is your choice for coyotes....300 yards and in. First things first, AR10 anything is heavy and you are going to struggle doing any offhand shooting, which down here in the south 'yotes have a tendancy of surprising you and you have to swing in on them and shoot quick. Unless you are a member of Seal Team Six or Ahnold Schwarzenkophenhager, it isn't an easy task!
I'm getting a little older and starting to realize I can't swing the same sized stick I used to. I spent the first half of my life running into things head first and the second half proving I could still pick it up.
If you're doing ranch/farm predator control from a fixed position that you can rest and swing on, AR10 all the way. If you're creeping in and out making stands, light to midweight bolt gun.
AR10 in 243, hoot to shoot but the dang thing is still heavy. Now the 6.5 grendel in a AR15 platform, more compact...lighter and IMHO a much better woods gun.
Bluebeemer nailed it. Look at the WSSM uppers out for the AR15, 223, 243 and 25. All put some juice down range for less money in a lighter package. That being said the 6.5 is as good a one gun for everything as you're going to find.
just be careful of the BlackRifleDisease(BRD) its infectious. Want to hunt hogs today, pop two pins and put on the 450 busmaster upper. Going deer hunting, pop two pins and put on the 25 WSSM. Going gopher huntin..2 pins and the 204 ruger. Kinda like "Barbie" for men
Good luck with the decision!