Keep in mind, the 29 whp gain is before 6500 rpm and there is almost another 1000 rpm after that so that is the midrange gain. The peak rpm gains at 7000+ rpm are probably less. It simply means the JoeZ exhaust helps the midrange torque a lot (and hence the HP).

JoeZ is a very credible guy. He typically never exaggerates benefits of his products. 18 - 20 whp gain is very common on the RCF because the stock exhaust is choking the life out of the car with only 1.5 inch piping diameter and there is the nasty 90 degree turn just before it is routed to the mufflers. With optimal pipe routing and over 1 inch additional diameter, it really allows the engine to breathe well at high rpms.

 

Yes there was drone, especially as you've heard around 2,000 rpm. It was manageable, normally I would downshift to 7th on the highway to get out of the drone range, and it was really only apparent with certain amounts of throttle input. I will say, towards the end of my ownership the exhaust developed a really bad vibration noise, not sure what it was, but I ended up putting the stock back on when I sold it.

Here is a vid clip of the glorious noise possible from the Joe Z..... I miss this lol.

 

This guy put JoeZ PTS exhaust and he put down 421 whp in 5th gear. Not sure if they are SAE corrected numbers or not

 

Exhausts, unlike children should be heard and not seen! The Joe-z sounds nice but I can't un-see it. If the axle back portion were blacked out and the tips were 1 to 1.5" shorter in diameter, it would be very nice. As it currently sits, too blingy for me. Just my opinion.

 

LOL...the children analogy is funny. I can see your point about exhaust not being conspicuous, but I personally love the look of the Invidia full catback especially in real life. The tips shape is like stock, but have the titanium burnt blue as it complements the design.