dont go with 3 chambers.. i have flowmaster force 2's.. with LT"S and offroad H pipe and its still pretty quiet when your just prowling around.. i wanted quiet and thats what i ended up with when i got the force 2's.. if i had 3 chambers i would really be bummed out with the sound..
when i got the catback i had stock manifolds and stock H pipe and i wasnt impressed at all with the sound.. you will want your money back if you are staying catted with 2 chambers.. I;m guessing that 3 chamber with offroad H will sound like a 2 chamber catted...
I'll tell you though.. i couldnt be happyer with my 2 chamber, its not loud enough to piss off neighbors when you idle out in the middle of the night.. but its loud enough with an equal sound to make you happy.. .. with some of these glasspacks out like magnaflows they are really loud and dont really have defonition to them.. just loud and annoying in my opinion.. look around to find your noise!.. hope this helps..