Im getting my cobalt ss s/c this week and i was wondering if is shold stay with the pioneer 7-speaker system or if i need to add a little more "thump".

 

It depends on what you're in to. For me it's plenty since I don't care what others outside the car hear.
In my opinion, it has plenty of thump for a stock system and will be flexible to all types of music.
Before you invest in high-dollar stereo equipment, you should at least see what you think about it for a while and adjust the settings to your liking.

 

W3rd!!