So on the way to work this morning I listened to "The fall of us all" by Steve Tibbets. Not sure how many of you know this music.. hard to describe.. world-jazz-fusion-electronic? It is basically a lot of percussion.. drums, cymbals, some really deep electronic bass, etc. It sounded much better than I would have ever guessed given the bad reputation the factory sub has. Maybe it's the alpine amp that is making the difference.. those little subs are really moving a lot.. maybe they will not last for long... they are not distorting..yet. The drums sounded great.. the sub allows me to turn down the bass on the head unit to -1 and now the door speakers sound much better. There were a few passages that exceeded what the sub could do.. however that has been my experience using this disc with many subs.. car or otherwise. Bottom line.. I'm getting impressed with this cheap little setup. For what it is cost me to do it's a great bang for buck. Between the amp and the used factory sub, I've got about $350 into it. It is nothing like my home sub.. but at home I have a $5K REL driven from another $10K or so of tube electronics. This still would not cut it of you are totally into Rapp / Techno / earth shaking / child scaring bass. Time will tell but this might be good enough for the commuter car..