Didn't sabre def. go out of business? I thought they got charged with breaking several import and export laws and had to declare bankruptcy... There website doesn't work.
Yeah, they also are under federal indictment and one of the things they are in trouble for is selling out of spec parts on the internet. The employees were taking the out of spec stuff they couldn't sell to Sam and selling it online.
For that reason and that reason alone I would not ever buy their stuff. I have no way of knowing if I got the good stuff or the junk without considerable effort and time measuring the thing. Definitely not worth the money in that case.
I second Colt for the best all around. I had a new one in the army and I couldn't tear it up easily. After tens of thousands of rounds, it would still shoot a couple of minutes at 600m. Not bad for a rifle that came with a $600 price tag on the invoice! It came with a blank adapter, a sling, and one mag. FN made the one I used in basic, I think they'd be a big seller but they don't make 'em for civvies. Those were TOUGH M16 rifles. NO finish at all left on them, shiny metal. But they worked just fine.
The rifle I am currently building uses a Satern barrel, JP Ent. bolt carrier, RRA two stage trigger, KAC free float rail, and that is about it. The rest of the parts are just quality milspec, like an AR Stoner buttstock, DPMS small parts, and Aero Precision receivers (cheap milspec like the first fellow said).
I'd stick with mostly milspec stuff myself, where I'd splurge is on the barrel and the trigger (but you can make a DPMS standard trigger into a GREAT trigger with a little polishing). The barrel more than anything else determines the accuracy of the AR --get a good one. Satern was the best I could find. The KAC free float is probably as good as the next free float system, but I like it because I have used their stuff a lot and it doesn't fall off in the field. I also have a ton of panels for them, so that helps. The JP bolt carrier is just the nicest I could find. At least it seemed to have the most attention to detail regarding the millwork. It cost $30 more than the next nicest milspec carrier with a bolt, but I didn't need the bolt so I went with the JP.
On the other hand, I have a rifle that I built to see how cheap I could build it. It got Oly receivers, an Oly rail (not as bad as I thought it would be actually) and an Oly barrel and bolt carrier. The internals are a mish mash of stuff I had in my box, the buttstock is army surplus M4 along with the pistol grip. The M4 carry handle (which it seldom wears) is army surplus, either Colt or FN. The trigger is DPMS left over from another build (4.5lb., crisp and just awesome, all it needed was a little work). That rifle shoots about 1.5-2MOA and has been very reliable. I use it for my HD rifle in fact. But I've shot enough through it to know what works and what doesn't. All in all, it cost about $400. It would have maybe cost $600 if I had to buy all the parts I used at once. For a 100% milspec rifle.
If you are doing this for reliability, you may be better off getting the Colt. Just note that when you build a rifle, getting it right is all on you. The best advice I can give on building an AR is to go and get the army armorer manual. The one that shows how to install barrels, the whole nine yards.
Having go no-go gauges are nice too, and you'll definitly need an action block, a vise, and a barrel wrench, as well as the appropriate punches. By the time you invest in all this, you could have gotten a nicer rifle... I'd only invest in the build materials if you plan on building more than one. Or try and find a buddy that wants to build one too and then you each get half the supplies or something.
Oh yeah, also stay away from the bolt on or set screw parts. Like gas blocks; hard to get a pinned gas block these days. That is because they are marketed to the tacticool crowd that hasn't spent a month under a rock in the rain. They are sold to folks that want to take off their traditional sight tower and replace it with a cool looking flip sight. But the selfsame folks don't own punches or action blocks so they sell them as bolt on pieces. Then they can mangle the old ones off and just bolt on the new ones for that tacticool look. FWIW, I tested a set screw gas block in the army. We just kept loading mags and feeding them into the rifle and pulling the burst trigger ten times, then reload. We did this for a few hundred rounds, let it cool, then did it all over again. After about a 1000+ rounds or so, sparks and gas escaped, and then it just blew it off the end of the rifle. End of that test.
And as far as flip up sights go, why spend hundreds of dollars for a sight that WILL NOT be accurate at distance? The KAC one is made for 600m, sells for $200, and may be good to 300m. And that is the best one. I haven't found a front sight that works at all. Any movement whatsoever negates the usefulness of the sight, especially the front sight. For the price, a backup reflex sight, one of the tiny ones, would be more useful. But what I do is install the regular sight tower. Then I just use the carry handle when and if I need it. It gets tied off on the rucksack, always there if I need it.
For SHTF, just look at what the army uses. Forget the AK, we don't live in a 3rd world backwater. As soon as SHTF, the borders will be locked down, the economy will stall. Good luck maintaining those AK rifles, better luck getting ammo for something you can't easily reload. As I recall, every maker in America makes an AR now. Were I in Russia or Africa, I'd go with the AK. Save the AK for the really bad times when all the AR parts run out... But you'd likely be the last man standing, so perhaps it doens't matter anyway.