Gen 3 Misfire P0303 Denso Plugs

Started getting a light misfire under hard acceleration several days ago. Yea I know its a prius and I really don't get too aggressive with it most of the time. Felt the misfire and also got the flashing CEL for a few seconds each time. I'm at 262K miles and I last changed the plugs at 192K so I had not expected a problem so soon. I ordered a new set of Denso SC20HR11 Iridium plugs which were the stock plugs that I installed at 192K miles. I got the wiper and cowl assembly out in about 10 minutes, and had the plugs out in another 5 minutes. I was surprised to find the center electrode of all the plugs completely gone. The gap was well over .080, new they are supposed to be .043. I put in the new plugs and also did an intake EGR clean. EGR ports were still very clean compared to when I did the cleaning at 192K.
Reading some other posts I wish I had purchased the Denso (4711) IXEH20TT since they are supposed to be double iridium, I will get them next time around.
Not sure if the previous set I got were counterfeit or something. I still stand behind Denso and NGK brands. This post is just to help someone out in the future.

 

Correction: Amazon details says Denso (4711) IXEH20TT and Denso 3444, center electrodes are iridium, grounds are platinum. I'm confused now. Oh well nothing new there.

 

JC91006, same exact plug at least by the part number. Denso SC20HR11. Maybe the angle and fact that the center electrode is gone make it look different. It definitely fixed the issue. If my yearly miles driven stay the same I should know in about 2 years if these last longer or not.