Ahhh sling can be the last of your worries. The GI sling is more than workable with practice for all sorts of situations. Practice with it. I was going to buy a fancy sling until I started practicing with the GI and then I changed my mind.

Has anyone said AMMO?

Maybe if you want a fancy M4 style get a railed forend. I recomend the Larue 7.0 I love mine.