With all the talk about which exhaust was the deepest Rhinehart or the V&H Hi-Output we went to Daytona over the weekend, I went straight to where Rhinhart was set up, They had just installed a set of the 4" slip on's on a 110, At idle they sound good then ask them to run it up to 3,000 rpm, sound real good, Then i went straight to V&H they had a set of the Hi-Output on a 103, ask them to do the same idle and 3,000 rpm, The V&H are deeper and louder at idle and at 3,000 rpm. so i'm going with the V&H Hi-Output. At 3,000 rpm the V&H are 103db, not overbearing but loud enough that the cager's can hear you.
I have never liked the sound of a 2 into 1 but V&H Hi-Output and the Pro pipe with the performance baffle sounds real good. But i'm going to stick with duals.