I installed this exhaust myself this week. I'm impressed, in terms of performance and sound. Maybe it is because I have the EJK as well. For the first time in my ownership of this bike, it sat comfortably at 80km/h - 50mph and just wanted to keep going. It was like it didn't require any effort to be at that speed.
It pulls well in all gears and acceleration is smooth. It is quite loud when you give it the beans. Good stuff.
I think these bikes are great. With subtle mods like these, and appropriate fueling, they perform so well. I'm quite sad that I didn't opt for something like EJK / PCV earlier.