Slow load? Why?
I carried autos (select fire and belt fed) for several years as a US Marine and later as an employee of the DOD and I never needed to do anything that way.
I lock and load my firearms either when I get out of the truck and in some cases when I leave my home.

I can see the reason to leave an empty chamber (or unprimed) in a few types under some conditions, like those that have small half-cock safeties. Those include the older lever actions and my muzzleloaders but for the most part I feel any rifle or shotgun that is not as safe as a military rifle or machine gun is not a gun I'd keep.

Yes I have a few exceptions like my older Marlin 30-30 and my old Winchester M95s, so those get carried in slick or steep country with empty chambers, but they are no quieter to load the chamber then my ARs or my M14, or my M1. I had a Benelli R1 in 270 Short Mag (sold now to a friend) that would shoot 1-1/4" and the longest shot I ever made on an elk in my life was made with that gun and it did just fine. And one thing I did note about the R1 was that is was actually very quite to load the chamber with. The nosiest one is probably my M1.

And as far as them not being as accurate, that depends on what you are comparing them to.

My M1 and my M14 will both shoot under 2 MOA. My ARs will shoot under MOA with most hunting ammo, and one of them shoots under 3/8 MOA. My 308 Auto shoots about 7/8" groups with ammo it likes and I have shot a few 5/8" groups, but I can't always get them that small. But I don't need to either.

Here is a photo of the very best groups I ever shot with iron sights in my life and it was shot with an AR15 in 6.8SPC. 100 yards. 4 rounds The one in the corner was my last sighter. My spotter said "come up one click and left one click and shoot a group". I had 4 round left in the mag.
Now I have shot a LOT of similar size groups with ARs but this one is noteworthy to me because I didn't use a scope.
[Linked Image]6.8 at 100 by .com/photos/156296479N08/]Steve Zihn, on [bleep]

To say the AR is not accurate is to have to give explanation as to what "accuracy" means to you. This rifle is not my choice for elk, but one in 308, 7-08, 338 Federal or 358 Winchester all would qualify with flying colors.