Brisk doesn't even recommend their LGS plugs for anything other than a stock s/c 2800. Since two different people at Brisk told me this I decided not to try them
I'm running TR6IX plugs right now, but have just gapped a new set of Autolite 104's to install tomorrow. I've had no problems with the TR6IX, I just change plugs often.
My last set of Autolites (AR 103) lasted about 10k miles. They are cheap and easy to get.