Just pulled the baffles on my Sil megs and I swear its quieter now than before.....it at least had more bite at idle thats for damn sure???? ??? Might be a touch louder when reved up but I was thingking that there would be a distinct night and day difference.
My full Arrow system is less "tinny" at idle with the baffles out, and I suppose that to some it would sound quieter. However, that perception goes away when I blip the throttle, and thus I'm keeping the baffles in to avoid the neighbors setting my home on fire (leave early, home late).
I think it's more a quality of the sound that changes, not the quantity, at idle. At WOT, that's a different story, as the system still sounds very good with baffles in (and keeps the peace).