My preferences is that ported box mostly give you port air noise rather the bass you want to hear... If you have a sealed enclosure, you get the best out of most subs... That's my two-cents...
In my opinion, both are good. It all depends on the sub and what kind of vehicle it is going in to and of course your own preference. I like them both, depending on the situation, my opinion is bound to change, but bandpass(eww....)//content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif
Ported boxes are more efficient, capable of reproducing lower frequencies and have less distortion than sealed boxes. For these reasons most recording studios use ported speakers. Also many manufactures of home speakers use ported boxs. although they are harder to build and can result in poor sounding bass if not properly tuned.
Sealed boxes are often used in cars because they are smaller, easier to built and have the best transient responce. The air inside of a sealed box will keep the speaker from over excursion which increases power handling. If you like tight accurate bass than you probably should use sealed. if your looking for high output and low distortion go with ported.
Band pass boxes can produce superior output but are tough to biuld and only play one note bass. Thry can also ruin your speaker.
Unless you can calculate very well and kno exactly all of the calculations for size id say dont bother goin for ported. Sealed works very well. Esp if your building the box yourself.