Well, I'm late to this party, but I installed a set to get me through until my next service and subsequent pipes and remapping.
Sounds healthier in closed loop and cut down the decel pop. Pulls easier at part throttle. Not yet enough mileage to judge efficiency by.
Easy install once a fellow Fat Bobber (Hotbird) told me where to find the junctions in the convoluted wiring.
This forum is excellent!
I'll be looking at Frankie Serrano pipes and TTS, just to steer clear of the pack. I think they'll look good, and if the dyno sheets Frankie sends me show what I am expecting, I'll be happy with the performance as well.