Bummer, M4 ramps are + $20. I was going to get a WOA 18in barrel but these are still slightly cheaper ($40 cheaper). I was holding out for the $200 barrels and was going to get three. The Stealth barrels are a heavy profile and similar to a WOA Varmint profile, correct? They would both shoot about the same groups? There are quite a few Larue barrels in the MOA challenge.