Monty sure knows a helluva lot more than I ever will. I think he recommends the MUR for more of a SPR/accuracy build but who knows. As for warranty, don't know what to tell you. I build my own and thus I am my own warranty dept. If you start with quality parts and know what you are doing, not much warranty needed.
My main point is you are considering very good quality so you will be happy no matter what you get. Might want to look at BCM etc. What is your main goal for this rifle?
Also $185 for BCG is a rip-off (perhaps it is coated). BCM and DD are $125-140 and they are great.
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