Anyone having/had plug issues with their '8'?

I'm still trouble-shooting mine to figure out my problem. Still getting hesitation/girgle at about 7000rpm's.

argh!!!!!!!!

I found a Mazda service bulletin at:
http://www.finishlineperformance.com/rx8/docs/flash_rf04-04.html

It doesn't address hesitation specifically, but does list alternate plugs for colder climates.