I am in need of some AR wisdom, I'm preparing to start my first AR build. This weapon will be used to shoot coyotes and various other four legged vermin. I have narrowed my choices of uppers to the RRA Coyote Rifle and the Bushmaster Predator Rifle. Does anyone own one or have a preference of one over the other? There is about $100 price difference in the two uppers, that will be less I have to spend on my trigger, stock, mags, and ammo. Any other suggestions? I will be building on a Bushmaster lower that I have stashed back.