Your're way wrong, plain and simple.
As you can see from my name, I use the RPG all the time.
It is FAR more accurate in this game (for shotting down hellis, long range), and it has much more damage than the noob tube.
This is the BEST Secondary Gun to use on Hardhat. When guys are in the concrete tunnel, they WILL die, unless they have blast sheild, even then 2 RPG's will work.
I have had numerous double kills, and even a few triple kills.