A lot of people knock the Lsw but I've love it, all the benefits of an LMG with reasonably fast reloading means that when the smg boys have run out of bullets you can just keeping on going. I got it gold and all the challenges without really trying that hard.
Some people love the Lsat but I'm finding it more difficult.
I disagree about the range. While playing Drone I cleaned the snipers out of the backof the map and fliped the spawn. I then set up shop and was able to snipe the helicopter pad with a regular sight.