To be honest, even with constant cleaning of the stock plug, it would end up looking quite fouled after every 300km or so. That is with the stock TPS voltage and rides lasting more than 20-30mins or even longer rides. The bike would run okay and never really showed any signs of trouble if I remember correctly. Only the idle was a bit erratic. And a lot of soot over the double electrodes, not sure why.
Then I swapped to the BPR6ES after reading the feedback given here on the forum. The idle RPM had increased staight after the swap, so I decreased it. After that, everytime I've taken it out to clean it up etc on service intervals as highlighted in the manual or just for inspection, the electrode part has never shown signs of running too rich or too lean. Always has shown me light brown/tannish tinge on the electrode, with carbon deposits only on the outer ring of the plug (Surrounding the electrode). I'm running the EFI silencer with the mechanical baffle out, leaving the perma-perforated baffle in it. The system has adjusted to it well, with rare-occasional backfiring.