E3 spark plugs?

[zuren1cs]

Anyone tried these?

E3 Spark Plugs

I'm doing maintenance on my Yard Machines lawn tractor and old IDC string trimmer. I already bought a replacement spark plug for the trimmer (Champion DJ8J) but still need something for the tractor. E3 makes all kinds of claims but I'd like to hear from people who may have tried them.

(Performance claims)
E3 Spark Plugs

Thanks!