Steve C.
First, let me recognize the superior level of customer service I received while my order was being processed. Nancy was very patient and professional in handling my questions and she did so in short order. no fumbling or putting me on hold; if she had to refer me to technical personnel, it was done quickly and courteously, and I got the answers I was looking for in a very timely manner. More companies should follow Hardened Arms customer relations model.
I ordered a .300 AAC Blackout caliber upper assembly, (16" barrel/15" Scorpion free float handguard/Nickle Boron bolt carrier group), and it is the best carbine upper I have ever purchased. It fits my lower receiver as if it were hand fitted - no gaps, no rattles, no binding, just a nice tight fit. My lower has an ACE ARFX stock and this makes for a very light, quick pointing carbine.
I have built or handled literally hundreds of AR platform rifles in my experience, so for me to be impressed says a lot about Hardened Arms products. This upper assembly compares to any major brand on the market in quality, it just costs a lot less.
My next AR will be from Hardened Arms.