What after market exhaust system for a 05' tC has the lowest DB rating???????

1st. Megan OEM set-up
2nd. PrecisionMuffler.com Axle back

i dont have any numbers to back it up. but my greddy sp2 compared to my buddy's stock exhaust (we both have trd s/c, but i also have the megan s-pipe) is only minimally louder with no rasp. i prefer a subtle exhaust and the sp2 is probably often mistaken for stock (sound only, tip is noticeably BIGGER). my 2 cents\