Fully automatic Light Machine Gun
This is a bit of a personal favourite for several reasons and seems to have the perfect balance for a LMG. It is powerful enough to dispatch targets without having to aim for headshots but at the same time does have the short burst accuracy to take down targets at some distance.
The recoil is manageable and predictable, however coupled with the handle is minimal. In fact after the barrel lifting slightly when you first fire, the recoil almost stops allowing continuous fire that is actually aimable and accurate.
The iron sights are very good allowing quick accurate aiming whilst allowing a good field of vision. Which is useful as you will be searching for your next target almost continously given this guns fire power and accuracy.
The RPD does work particularly well with the double tap perk which makes the firepower of the gun almost ridiculous. You can take down targets at a fair distance easily and quickly and I have achieved some very high scores with this combo.
You can either camp down in a good vantage point and as long as a sniper does not spot you, you will be almost invincable. However I also find myself reaching for this gun if my team is being over run or pushed back. This is because the massive amount of accurate firepower you can dish out can stop enemy drives in their tracks.
The RDP can also be used very effectively offensively hunting down your foe, almost like a heavy assault rifle. It has the accuracy as well as the heavy rate of fire to punch through held positions or repel advances.