I'm only familiar with the standard A2, but I'm in search of my first civilian "AR" and would like to be different. I'm also not familiar with optics, but I like the ease of a fixed power and never warmed up to the "assault" type of optics. Is it rediculous to put a 6x42 traditional scope on a flat-top carbine or does that kind of scope really beg for a 20" flat-top? Also, the heavy stainless barrels seem like a good idea. What's the deal with heavy barrels on an AR? My application will be lots of range use usually 100 to 300 yards and just general preparedness.