NGK ZFR5N plugs, yes or no?

These are the plugs I've seen recommended after searching the net, but when I went to order them at Napa my friend who works there was reluctant to get them for me and told me to go with the regular ones because he thinks these ones just aren't correct and won't work. Now he's got me doubting about using them so I figured I would ask here to see if any of you guys are using them, or if anyone has had trouble with them. This will be for a 1970 225.
Author: admin