did you see the price tag? $25 each. they used to say the slit fires where the best because of the split alternated electrode surface area. but they didnt say that after a 1,000 miles that gap would become filled with sludge and it performed worse than a regular plug.

with such small components, i wonder how they would stand against rough driving, bouncing, the occasional hard hit on a pot hole, cold/heat expansion and contraction, premature electrode wear? .

i didnt have time to read the article, maybe this is already addressed there.