In my opinion this is the best piston upper that will fit nicely on a AR-15 lower. Ease of cleaning and great design are there. It's also extremely reliable. Cost is another factor. You can get a complete upper for less than 500 US dollars. That's without a rear sight. That point doesn't matter to me as I have a scope on mine. It's really well made. Nitride finish cold hammer forged 1:7 5.56 Nato barrel. Only bad thing about it is it's fairly heavy. I think this is about the same weight as my 20" A2.

If you're looking for something a bit different pick one up.  I love mine.
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Definitely the best for the price. They get great reviews, I looked into them for awhile. Enough research led me to PWS, which I personally believe is the best piston upper that fits nicely on an AR15 lower (biased) lol but to each their own. Also, O-H!