Ok Jimmy thanks for that, I have seen this before and it was one of a number of items on the net that said fake NGK plugs are bad but if you look close at all of them they are made and distributed by NGK, I have yet to see ANY report of someone who has had a problem with their plugs genuine or not, most tales are word of mouth but when you try to search it out there is little or no evidence to support the premise that a spark plug has actually let go in the way that folks say ie up through the tank or into your leg let alone a dent in your bonnet (hood for the colonials!) If you can find someone who has actually had any of these problems get them to write a report so we can all hear and see what damage,if any, they might be capable of, cos right now I remain to be convinced that the photos on the NGK advice aren't just from engines that have been neglected or driven hard, if you look at the stills in the video all the pistons are from cars.
PS as an aside if you look at the final still of a piston and plug that they show the plug has been melted and the piston holed right through, I bet a few on here that own 2T bikes can relate to that !