I don't waste my time with expensive bling race plugs. Again, i'm just an average weekend bike beater, so I could potentially foul a standard BR8EG $5 or a $12 go-fastest plug, i'll stick to fouling cheap plugs. IMO plug performance is more directly related to proper crisp jetting, than swapping plugs to alter performance. Now that I have a good understanding of jetting, I can't even remember that last time I fouled a plug..