Which of these brands of iridium plugs, if either, are superior in the G35 and why?

Please leave price out of the equation.

I'm looking for replies from those who have specific evidence or knowledge based on experience rather than brand loyalty responses.

 

I've always used denso iridium in all my cars, denso iridium is standard in lexus

 

i have denso's, but frankly i felt no difference when i switched

 

ngk

 

I would stick with the NGK's. (and did)

 

There is data that NKG Iridium perform well compared to what we have stock... but haven’t seen the "side by side" that you are asking for.

It would be beneficial to us all (you included) for you to test and post results.

 

Well, I switched from Denso iridium with about 40K miles to HKS iridium about the same time I installed the HKS DLI II ignition amp.

My impression is that gas mileage is about the same but the car feels a little stonger. But I can't be certain so don't put much credibility in this.

Unfortunately, I'm about 100 miles from the nearest dyno, so test results won't be soon coming.