Spark plugs are one of my soap box items........
Properly functioning, spark plugs will not make you any more power........ I don't care who made them. It's one of those items that has been developed to top of it's performance potential and doesn't have much room to move ahead. The development room that is left with them is in robustness and longevity.
With that said, the E3 plugs use the multiple ground strap scheme, which I like, and has been used very sucessfully in aviation and racing since the 1940's. The idea behind this is that you have a better oppotunity to have maximum spark performance through having more options than one for the path of least resistance. You also have less of a chance of having a misfire.
The E3 plugs are not the only plugs on the market that use this design. Bosch has 2 and 4 strap plugs, while Splitfire has a forked single strap (I hate Splitfire plugs and wires as they were engineered to sell rather than to perform properly).
The best thing you will see from these plugs is easier starting, more consistant spark related performance, and hopefully a longer plug life (nice to have in a two stroke). I don't know for sure what you will see with these plugs in a Banshee as I have not tested them. However, I do think that they are not as expensive as some of their competition and at their price point, they are worth a try.
Let us know what you think of these things after you have run them for awhile.