Yes, I have done a bunch of it. My first question is what did you get? If you got ultimate or extreme - that's not sound deadening that's vibration dampening.
doors - (makes the speakers sound a lot better and gives the doors a nice solid feel)
hatch - helps reduce exhaust and booming noises
floor - helps with road noise at speed and filters out some of the higher pitched engine noises.
The hatch will be effective for removing the exhaust drone. However, you still need a sound blocker. Extreme is for vibrations - the vcomp will block sound.
That being said I just put down something similar to extreme (RAAMat BXTII) + PS ensolite in my hatch and it reduced a lot of the exhaust noise (oem exhaust). It's all additive though, the more you do the better it will sound. I would start with doors and hatch.