yo, people! anyone ever tried upgrading the stock Bose subwoofer on a 1998-2001 A6 (mine is a 2.7T, but I think all a6s from these years are same)? I want to get something to fit the space where the bose sub fits, I'm wondering if it is simpler to build my own box to fit using the factory sub brace or should I just look for someone who makes a mold? what would sound better and what would be cheaper?

pour in your opinions,
V