I have the HF model. It has worked like a champ for years now. Just be sure to blow the plug out with a little clean air before reinstalling it to dislodge any errant glass beads that might make their way into a ring grove. When I was in high school auto shop we had one of the old Champion plug stations, we used to hook the test lead up to the metal workbench it stood next to and wait for some poor sucker to come lean on the bench. That all ended when some dummy (not me) decided he would discharge the coil into the bench when our grizzled old teacher leaned on the bench. We never saw that neat old Champion plug station again, I'm guessing it found its way into the school dumpster.I've been meaning to get a plug cleaner for years, and didn't know they were still available new, as I recall using the older benchtop Champion models decades ago. Any time I've seen one of the older ones, some silly price has been attached to it, so I just let it slide.
However, seeing the HF one got me looking and those cheerful Chinese are making them now for 25 quid delivered.