Am building a SPR, but I don't know what barrel manufacturer to use. The market for a 18" barrel with rifle length gas system isn't really big, but I would like some advice. I'm trying not to brake the bank, but at the same I know you pay for what you get. Can anybody point in the direction I need to go in. I'm thinking between $250 for a Wilson Arms air gauged stainless steel, Rainier Arms $299, or $260 WOA. If anybody can think of another. Rand that is good and good price please let me know.