I've never quite understood the multi-tipped plugs, the spark will travel the path of least resistance, one tip at a time, not all of the tips at once (like in commercials).
For those looking to find NGK plugs cheaper, try
RockAuto Auto Parts . Autozone has them for
$8/plug on my '87 CRX HF, and I got them for
$2/plug from RockAuto. Shipping with a load of other parts was only 6 bucks or so, I don't quite remember. Never the less, massive deal.