I like my LMT MRP upper and it shoots well as your ability and the ammo you put in it. It has some pluses and minuses. On the plus side barrels are easily changed and the rail is one piece. On the negative side it requires a special tool (which is included) to change the barrel, the barrel isn't interchangable with other systems and weight might be on the heavy side.
If I used it as a tool of my trade the barrel would be a worry because it isn't interchangable with other systems.
http://www.lewismachine.net/product.php?p=56&cid=8
For plicking and trips to the range it is overkill but I love it none the less.
I also considered Sabre Defense:
http://www.sabredefence.com/commerci...ocus=upper#spr