Make some coffee or pour a bourbon before you start reading:

https://www.ar15.com/forums/AR...e/118-677135/?page=1

I never put much weight in the chart. As noted in other posts, I consider the chart a floor level of component quality and a banner for Colt enthusiasts to waive. The features listed might be very important to many AR owners, but I prefer a different AR. The chart is outdated now, and likely was to a certain extent from the beginning.
- I like 1:8 twist .223 stainless barrels that are not chrome lined. Accuracy means a lot to me. A 5.56 chamber, 1:7 twist, chrome lined, milspec barrels aren't in the same league. And a mid-length gas system on a 16" barrel is better than a carbine-length gas system.
- My vision isn't good, so I use optics or red dots. Front sights mean nothing to me.
- I want a free floated barrel with a quality rail. Handguards and the lack of free floating are negative features in my book.
- In my years of precision and multi-rifle competition, I haven't seen Colts at the top of the leader board. Now I realize they have done well in high power matches, but not in my preferred game. From what I know in 3-gun matches, Colt isn't the AR of choice.

As IndianaBoy stated, the core of an AR is its bolt and barrel. I add further that the receiver must be good, and the barrel must be properly attached to the receiver. ARs are so modular that many components have little relationship to the roll mark on the receiver.

For years the webz talk has been that rifles scoring well on the chart are more reliable. Maybe, maybe not. I don't see much in tangible evidence. As IndianaBoy stated, put a few hundred rounds through an AR -- at various targets, at multiple distances, from different positions, aimed fire, rapid fire, different types of ammo, multiple magazines. This is how one determines an AR's reliability. Reliability & utility doesn't come from slow fire from a concrete bench at 50 yards. Repeated mag dumps are for youtube clicks, not utility. The majority of stoppages I see are from ammo quality, mag quality, lack of lubrication, and lack of cleaning.

The average AR owner likely never puts more than a thousand or so rounds down any AR they own. Then the AR spends quality time in the safe, while the newest & bestest AR gets a thousand rounds. Then the next uber AR comes on board. Then again, and again. Reliability comments from these folks -- I take with some salt.

When I see an AR owner who shoots enough to wear out a barrel, I listen. When I see an AR owner who shoots enough to wear out bolts, gas tubes, gas blocks, or triggers -- I listen intently.