i was told that if its just for show and u dont ride much then it dont matter. but if u are like me and cant stay off of it then u dont wanna go with that pipe unless is has something in it for back pressure... i painted these bikes here, the zx14 has a baffle in it...
this busa has just a straight pipe, no baffle
and mine is a straight pipe no baffle either..
what i was told is, the shorter the pipe the worse it is if you dont have back pressure, or packing in it. he said mine was ok because its long and the opening is far enough away from the motor. on the bulldog busa, if you put your hand near the rear of the pipe u can feel the air gettin sucked in. thats the part that damages your motor. if u can feel the vacuum, the engine is suckin in that air
look for a pipe that is short, but has back compression and u should be ok
as for the noise, depends on where u live and what your neighbors are like..lol you can put up with the growl yourself, just get ready for complaints if you sit in your driveway revvin it up..it will pop a few ear drums standin too close
just my two cents, but get a second opinion, im just a painter..lol