Aero Precision just introduced a new M4E1 upper receiver option. This is their first non-NFA/non-pistol M4E1 upper available. It sports a 16″ midlength barrel and their 15″ EK-15 KeyMod Handguard.
I have one of their M4E1 uppers in hand for review and I can confirm that it is a very slick system. It is more than rigid enough to properly support a 15″ handguard and assembly is a snap. Stay tuned for the full review.
This new upper is available at the introductory price of $350 which is a solid price for an upper, especially an upper with a well sorted out rail system. Check it out at Aero Precision.