First these flashy band pass subs with the plexi are mostly about flash and BOUM. Look at all the cheapo chrome used.
You better get one JL Audio woofer in a sealed 1-1.5cu ft box driven by a quality amp than this thing.The JL Audio will be much tighter,reach deeper and provide you with great sub bass qulaity.
I know subs(have 17 subs home,yes 17 subs) and these cheapo flash boxes come last when sound quality is paramount. In fact I would stay away from band pass designs as thye cover a very narrow freq range and often(too often)sound one notey.
For quality subs JL Audio is the big cheese,and you do not need a W7 series to have quality subsonics.