universal compered to true catbck

hey i was wondering if a universal apexi n1 muffler on custom piping from the cat and back would sound any different from buying a true apexi full catback kit. and does any one know how loud apexi is in decebels.

you know what.. i had a cat on mines then got it removed.. its not an apexi but it still sounded the same with or without it... so based on that i would think it would sound the same but i could be wrong.. its more of the resonator that affects the sound in my opinion