5.45X39mm

Right now the ammo is cheap, from what I hear from a few AK owning friends. But who knows what the future holds for imported ammo. Between the two, I would stay with the 5.56, it's more lethal with the right ammo, has much more variety in rounds you can use/reload, and can be found just about anywhere in the U.S., and has proven to be quite accurate. They also make an AK in .223 if that's what your after.

I agree. Soft points like the 55 and 64 grain soft points in the Federal TRU line are also very nasty and are fairly cheap. They both fragement violently and early. The TRU soft points have cannelures and the jacket extends all the way to the tip to avoid gumming the feed ramps with lead. The Federal Tactical 62gr bonded soft point expands completely in the first two inches of penetration and retains almost 100% of it's weight, even after windshields. Between those and the heavy JHP's like the Hornady 75's they are far superior to the 5.45x39mm.

Of course, the 6.8 is superior to all of the above....

I don't like to bash a brand, but I had a Model 1 6.8 upper and it was not very good quality. Parts were cheap.

I would wait and get an upper from a company like RRA, Stag, Bushmaster or Bravocompanyusa.com. As long as you have a lower to put it on you will be okay.

DPMS has tight chambers. Even the one's marked 5.56. If you ream them out with a true 5.56 reamer they are okay. When I went to Colt M16 armorer's school Dean Caputo (instructor) had one of the reamers and explained how some brands did not have the correct chambers which lead to extraction problems once the gun heats up. And that is not a good price for a DPMS, IMO.