For those who bash the Bosch Platinum +4 plugs, these came out after 60K miles. The only reason I pulled them is that the car has recently started taking a couple of seconds to start, where previously it was almost instantaneous.

The #2 plug, front row, left is a little wet, which hints that maybe that injector is not holding pressure. Other than that, all of the other plugs look very nice.
And for the record, I think the NGK plugs are also very good.

 

yea....i had a bosch spark plug break....the electode shot up into my injector...i am sure it was a freak accident but I will never use Bosch plugs again after that

 

I've been a Plus+4 fan from the get-go. First had them installed in my 3rd Gen Max at 165K, and when it reached 303K about seven years later, I decided to put it up for sale.

Even though the Max was running strong just the way it was, I decided to change the plugs. To my surprise, the electrodes on all six plugs were free of any oil or carbon buildup. They all had a light, uniform glaze on them and were evenly worn down.

The amount of wear on the electrodes was a lot less than I expected. In fact, the gap came out to be between .038" and .040" (depending on where the measurement was made). The plugs came set with a .044" gap.

So, after nearly 138,000 miles of use, they were still in great shape, and still in the Max when it sold.

Since then, I've got Plus+4's running in my I30 and in two 1995 Acura Integras. One of the Integras has put about 110K on its first set. Even though I could probably get another 15-20K on them, I am going to replace them with a new set.