Wal-Mart sells Johnson/Evenrude 2 cycle oil for about $17 a gallon. I see Penzoil for about $11, Wal-Mart brand for $6 and Bombadier for $20. I have been using the Johnson/Evenrude oil, should I stay with it, or are any of the others just as good. Also, if Bombadier bought out OMC, why is...