I've had five different exhaust configs on my bike: Stock, slip-ons, V&H
Longshots, Road Burners, and a Cobra 2-into-1. I've switched between the V&H and Road Burners and the Cobra in rapid succession the past month to see which one I want to settle on this season
and I'm going to leave the Cobra 2-into-1 on it for performance.
So, my thoughts are that the config -- i.e. 2-into-1, duals, drag pipes, or 2-into-2 with a crossover (like stock) have more to do with performance than brand. Big, open drag pipes will wail on top end but you lose so much mid-range it's just not worth it to me. Lots of the newer 2-into-2 pipes incorporate a crossover (like V&H Big Shots, I believe, as well as some Cobra models) that really boosts the mid-range.
For me, after experiencing the performance of the 2-into-1 pipe, I just hated going back to the soft mid-range of either of my 2-into-2 drag pipe setups. I thought I liked the sound of the Longshots better, but after repacking the Cobra silencer/baffle it sounds really awesome! Deep bass tone, doesn't really bark until 1/3 throttle, then all hell breaks loose
I'm stickin' with a 2-into-1 setup for now.
By the way, I'll sell the Road Burners: $150 + Shipping. They have some extra baffling in them that can be adjusted or removed. They are in reasonable shape....black, staggered, chrome end caps.
Let me know,