if i had to do it again i would still buy the ids-2 pipe. the wb and ids-2 sound almost alike. as for adding and subtracting disc for top end or bottom end, it also changes the sound the more disc you have the louder it is, the fewer the disc the quiter it is. my buddy has the wb pipe and i am not very impressed with it at all.

 

Does the Supertrapp IDS2 come with a spark arestor for the 400ex?

 

yes it has the spark arrester on it,