just put the Excelon 8" in last night, and "temporarily" plugged 1 of the stock coil wires into it. Big difference, not so muddy, hits the punches on both Black Eyed Peas and Tool. Next up will be to add the Rockford Fosgate PBR300X2 in line behind the stock amp. Because the RF takes a speaker level input, I can actually put this behind the stock amp to boost the power to the sub. The amp is also bridgeable to 300 Watts mono at 4 OHMS, and 4Ohms is what the sub is. The last thing I liked about the Excelon is the carbon fiber diaphram (no need to cover...) Will report back on changes with the in line amp. Once I have apples to apples comparison, I will then fill the box with polyfill to do a real comparison by changing 1 thing at a time.