Hi. I'm considering purchasing the BSW Bavarian Soundwerks subwoofers and trunk enclosure for my E46 330i. It's $860 bucks but is claimed to custom fit in the trunk under the deck lid for space and OEM appearance. I'm interested in how it hits and the overall sound quality. Does anybody have this system or any successful enclosure information? If not BSW's product; another application/brand... I'm open to all ideas that require MINIMAL modification to my machine. I have the HK audio package and I'm craving more bass! Please help me! Thanks for reading and contributing-Cheers!