NGK D9EA

Does anyone run NGK D9EA plugs in their XJ550? The book calls for D8EA so these are supposedly just a cooler plug. I don't need to change my plugs right now, but I was just wondering if I could put these to use some time.

I actually was trying to order some plugs for my new to me, 2002 FZ1, and the place I ordered them from sent me these instead. I should have received CR9Es. When I called them to tell me they sent the wrong plugs, the girl who answered the phone tried telling me these were a suitable sub. Not so I told her, and I got that information straight from NGK. She then took my VIN and phone number and said she would call me back. She then calls me back and says they are sending the correct plugs and if I could send the ones I got back. I said sure, as long as they send me a pre-paid envelope. She didn't appear to want to do that, but said they were still sending the new plugs. So as far as I can tell, I have a new set of plugs that I don't normally need.