After playing with spark plugs on the dyno, we found a plug is a plug is a plug, as long as you have a plug in the proper heat range. We used nothing but Champion in the drag motor and never had any issues. At the shop, we could buy Autolite race plugs right, so that's what we used in the motors we built.
I remember a few years back (well, 11 years, to be precise) a bunch of members on a Dodge Dakota forum were talking about how they were increasing gas mileage by switching to Autolite plugs. I've always recorded the mileage on all of my vehicles, so I posted up the results I was getting and made the change to Autolite. And saw exactly no change, whatsoever. The truck barely had 3,000 miles on it when I made the change and those same Autolites are performing just fine some 76,000 or 77,000 miles later (yeah, I don't drive much), so I've no complaints.
The only plug I ever saw I didn't particularly care for were the platinum tip Bosch plugs. The center electrodes were very small diameter and created a very tiny flame kernel. We ran them in some of the old Buick-headed small block drag motors we built at the shop with no problem, but I never tried them in anything else.
Don, that V-cut center electrode doesn't do much, because (everyone say it along with me) current always takes the path of least resistance. Air provides resistance, so the edges of the center electrode will be what are arcing to the ground strap. If your ignition system is hot enough, you can get a clean burn with surface gap plugs, which have no ground strap, at all. Sometimes, when compression is vital, you don't have room for a ground strap <ahem>, so surface gap plugs become necessary.
