I would almost vote NO on them. Most new design spark plugs are just a gimmick, and aren't worth the extra $$$$. But in the case of the E3... they don't seem to have the spread of heat ranges that NGK does. Personally, I wouldn't put one in my ski. Not to mention that 2-strokes eat plugs... so why spend the extra $$$$. A spakplug alone won't make an improvement in performance.
The only spark plugs that are worth the extra $$$ are platinum plugs. BUT... only in a modern FI car engine. The hard electrodes will give an honest 100K mi, where conventional plugs will start to wear in 30k.