You know, over the last 30+ years I've never used any other spark plug brand than NGK's. I do know Champion plugs suck, but I think the only other brand I had any contact with was an Autolite plug in the used lawnmower I had.
I'm keeping my Iridiums because I know the bike runs better. Your link also states his bike ran better. Also in your link the problems with the Iridiums were because the owners used the wrong gap, as stated in the link. The link says to gap Iridiums at .035 minimum. The spec for the VN750 is .036 gap, again agreeing with your link for best performance.Please get your facts straight before calling bull****. There is more energy (heat) in a spark from a spark plug that has a higher arc over voltage. Smaller, thin-wire cathodes of platinum and iridium plugs will arc-over at a lower voltage. If you are more of an applied-science person, then there are dyno runs posted online comparing different plugs and ignition systems. If your bike runs better with $12 spark plugs, that's great, but it indcates a breakdown somewhere in your ignition system, or a faulty factory design.
If you buy the U-groove argument from Denso, well, you don't need platinum to make groove in your electrode.
Here is a link to a random post with some anecdotal statements.