so Im in the market for a new rifle and Im having a hard time deciding on what 556/.223 chambered rifle I want(already know I want a m1a for 7.62/.308). I really like the look of the sig 556 swat. Products & Services but I cant really tell a difference in it and a ar that I would/could build myself except price? can someone tell me the differences? anyone with experience with a sig 556? likes/dislikes? suggestions on which one? I know that it would probably benefit me more if I built it then I would know my rifle much better that way.