New E3 spark plug for 627

[steve-wis 637]

I had trouble starting my 627 the other day to mow the grass, so decided it was probably time for a new plug. I was in WalMart so picked up one there. It is called an E3 plug, supposed to be more efficient and let you use less gas. The electrode is shaped like a horse shoe, a half circle, otherwise looks like any other plug. I put it in and the tractor starts and runs great. Has anyone else used these plugs? Any feed back, good or bad?

Appreciate any info.

Steve