The one I used is a cheapie from Ebay. If you used some grille cloth behind it though... would be a great OEM look. Even without the cloth I am pretty happy with it though.

http://i370.photobucket.com/albums/o...C_0035%202.jpg

Looks great! Considerably better and more OEM than that eBay pic.

This site has saved me a lot of research time and it's a good source of opinions and experiences. I thought I'd throw my two bits out there as a new member. I had an 8 inch powered Bazooka tube that I originally had in my 993 before upgrading the sub. The X5 stock stereo was good enough that I added the Audiovox Media Bridge ($150 + $50 install) to integrate my iPhone/ipod and added the Bazooka ($40 install) to the existing system and threw it in the back. For me, that was a good balance of $ and sound for the X5 as a daily driver shuttling kids/dog around and running errands.

But having just finished the stereo project on our e30, I thought about adding a 10" sub to the X5. With technology getting better and cheaper, I thought this $100-$150 option might be a good one instead of spending $600+? on a BSW system.
BassLink - Infinity US
or P300-12 - Punch Single 12" 300 Watt Amplified Subwoofer | Rockford Fosgate®
for less than $200.
It won't thump like the e30 but it could come close (I think) to the BSW 8" (although It definitely can't improve on the fit of the BSW).

I like a subwoofer that is a custom fit enclosure to fit where the OEM system resides so that no loss of rear cargo space is encountered. The JL stealth for the X53 fits well and sounds incredible in the X5. Yes it does cost more than some of the aforementioned subs but custom fit and performance is always going to be this way.

so whats your review on the sound quality of this?
its an amazing price and good looking box (which sadly will be hidden)

I would find a "sacrificial" side panel at a wrecker and cut it up. that way if I didn't like how it sounded / looked, I'd still have the original to reinstall! Ive been lazy and haven't installed my sub yet, I think its the longest "subwoofer install in progress" in history! lol! might have to get on it! thanx for the push!!!

So where y'all placing your amps?

Looking for ideas as I am bit by the bug and planning to upgrade the low end with a Polk MM1040 in the stock box and maybe go all out with a full active front stage which will have me needing 5 channels of amplification.

I want to have it all hidden and been pondering where to put the amps for a while now and I'm stumped!

I placdd my (subs) amp behind left rear removable panel

if my spelling sucks in this post its cause im typing on a tablet.

No worries CW, not a gramer natzi. :)

Yeah thats something I forgot I saw somewhere, thank you for bringing that up! So an amp there wont hit the CD changer and the bracket? Been looking at amp dimensions and they run about 2" tall nowadays.

You'll need to remove the CD changer and bracket in order to install the amp there, unless you can find a small amp that you can rigged to be mounted on the extra slot(s) above the CD changer. The alternative is to remove one of the floor plastic trim and put the amp there (I believed this is how Bavsound recommended on amp placement on their install) - But I'm a stickler for having all the stock pieces in place.

I'm intrigued and is very temped to update my setup to this (inexpensive box that looked fairly well made) - will definitely free up a some of the trunk space back. But too lazy to move my amp over to the other parcel (currently resides in the right parcel where the stock sub is located).