I built one last winter. Aero Precision lower, MAS Defense upper with 20" barrel, 2 stage trigger from Tom's Tactical.

At that time there wasn't much on the market for ammo and could only get the 75gr fmj's.

It shot decent (MOA or less) out to 450-500 yds but past that I was having issues with the wind pushing things around.

I ended up selling the upper and getting a 350 Legend that I can use for deer hunting in the Midwest (straight wall amo state). I have a tack driver .223 for coyote hunting so wasn't out anything selling the Valkyrie.