Well, my subs use 15"/12" active along with a 15" passive...I guess that puts them in the vented camp and I don't hear any problems...but, this is what Sean had to say in another post regarding the advantages of a sealed sub:
"The one advantage that vented designs offer is that they will play louder. Since this is not a major concern of yours, you can take major advantage of the improved transient response, increased damping, lack of overhang and ringing, slower resonance, more controlled output at resonance, etc.... of a sealed box. You'll also get less "bloat", which means you probably won't annoy the neighbors as much".
Sounds like sealed may have the upper hand?
Dave
"The one advantage that vented designs offer is that they will play louder. Since this is not a major concern of yours, you can take major advantage of the improved transient response, increased damping, lack of overhang and ringing, slower resonance, more controlled output at resonance, etc.... of a sealed box. You'll also get less "bloat", which means you probably won't annoy the neighbors as much".
Sounds like sealed may have the upper hand?
Dave