I've never had a decent car audio system, but a friend turned me on to Crutchfield when the factory HU in my 02 Protege failed. The master sheet and tools made it so easy to replace, I went on to replace the front speakers with a Crutchfield recommendation, then the back ones as well. Still lacking bass, I started looking at subs. I didn't want to spend a lot. I ruled out the MTX small sub because it has no grill and I have to put stuff in my trunk. The cone is stiff enough, but I worried about tearing the surround. The small B-8PT got good reviews, but one reviewer said "not as much punch as the B-8P." Since the footprint is about the same, and since the bandpass SW is a little cheaper, I decided to go with it, knowing if it didn't work for me I could return it. Still tweaking it, but very happy with it. The SW allows you to get more bass with less volume. If you are into rap, or like to play music so your ears are ringing when you get out of the car, this won't do it for you. But classic rock and jazz (e.g. Boston, Kansas, Sade, Steely Dan, Yes, Yellow Jackets, etc.) played at comfortable level, it really fills out the LF and has nice, tight, punchy sound. Adds a lot of clarity to bass lines, bass and lower drums. I'm very happy with it. Thanks, Crutchfield.
Pros: Aesthetically pleasing overall. Carpeted is glued down nicely, and the embroidered (not painted) "Sound Ordnance" symbol looks classy. Fits in the trunk without taking up all the space,. Fills out missing LF for music at moderate levels (I don't turn the volume much above 22 out of 35 max).
Cons: Some screws are driven in a bit crooked, evidence of hasty assembly (which probably helps keep the cost down) - not a big deal since it's hidden from view & you have to look closely to see. The connection slots are a bit narrow for spade clips for 8-10 AWG wire (which is what Crutchfield recommends for this Sub), & I had to use a grinding wheel to narrow them before attaching them to the wire so they would fit the slots - not a big deal if you have grinding wheel, but spades won't fit w/o mod.