I have the Cobalt 816's. What is the purpose of the "spunge" type thing that is supposed to go in the port? Is it necessary, will it help or hurt the sound at all?
IN or OUT will not hurt it, the bungs are just to block the ports, a purely optional function. If you find the bass from your speakers "boomy" or "harsh" stuff it in there Mr Bunghole, if it is too muffled or stifled, then keep the ports clear.
It's optional to diffuse air flow from your port if you have the speakers too close to the rear or front wall. This will help with bass peformance and prevent it from sounding to bloomy or bloated.
It's good, I'm still breaking them in. I want to get a Outlaw amp sometime this year and a better sub to complete my audio. And maybe next year a 50" plasma.