You will need a tune. My ECU started throwing lean codes from the upper sensors when I put them on. The tune corrected the AFRs, no more codes.

For me, no the exhaust isn't too loud. This is such a subjective issue it's hard to judge what is just right for someone else. I do experience drone from ~2000-2500 RPM, fwiw.

I wouldn't worry about the heat. I ran with the headers and cbe for a year before I got my tune. A month of that was with stillen G3's and a M370 intake. No codes were thrown during that time.

The only word of caution I have about the headers is that the primary O2 sensors are relocated underneath the car where they are more exposed to damage potential. A few months back I ran over a cone at AutoX and as it went under the car it hit the primary O2 sensors can caused both to fail. Please keep in mind though that I haven't seen anyone else have this issue.

What part of Ohio are you in? I'm in the Toledo area if you want to hear it in person. Also check out the Ohio G/Z club on facebook. There's a lot of knowledge there also.

Yeah, the loudness of ones exhaust is very subjective. I have the PPE LTH + 12" FI CBE. To me it's just right, not too loud and not too quiet. It wakes up the neighbors at start-up but settles into a nice audible rumble. The level of noise depends on how much you tip into the throttle; anywhere. And the noise will penetrate the cabin. I almost got the non-res but I'm glad I didn't after living with it for a while. Also, I don't have a tune and never got any kind of SES light :knocks on wood: