Aside from the couple of Champions that I got that simply were DOA, I was at my friend's shop right after they discovered a Champion electrode simply fell off into the cylinder of a newer car (Hyundai or Toyota, I just can't recall what it was). It was a brand new Champion plug as spec-ed for OEM parts during the scheduled service (60K type service). The electrode just dropped off as the customer was driving her car home from the shop and brought it back in. Destroyed the cylinder. They won't use Champions again. And considering my Ferrari mechanic buddy also told me to stop using them (for the DOA issue, which had plagued him in servicing cars for his Ferrari/Alfa/Maserati customers), I can't recommend them.
Champion was bought out by Cooper in '89 and then absorbed into Federal Mogul in 1998. Since then, the brand has gone downmarket. Champions are half the price of other plugs, and the quality reflects this.