I had been searching the Aero Precision DTOM receiver set for a while since Aero Precision sold out of them. After reaching out to an Aero representative and being informed that there wasn't a schedule to restock these items, I decided to look elsewhere. Luckily Arm or Ally came up on my search! The product was everything I would've received from Aero Precision and a little bit more, a FREE matching DTOM patch! Fit and finish is also perfect. Arm or Ally also came in clutch with a lower price than what was offered by Aero Precision. The only reason I didn't give 5 stars was due to the FFL verification process. While most companies are willing to contact and verify FFL information prior to shipment, not Arm or Ally. Not only that, but the FAQs clearly states not to email asking if they've received FFL info and that they would contact the buyer in 3-5 days by email if FFL info wasn't available. I'm just glad I wasn't in a hurry for this build as it did take about 2 weeks for everything to work itself out and shipment to take place. Also, no phone contact available. While typically responsive to emails within 24 hours, a simple 3-5 minute phone call would've been a lot more convenient. I also did not receive the pins or set screws that are supposed to be supplied with the M4E1 lower. Thankfully, Aero Precision does keep these in stock and I was able to obtain those from them. I was just too impatient for the potential 24 hour wait time on emails from Arm or Ally. Response was faster once or twice but for the most part, don't expect a response until the next morning.