Pops, the Quicksilver brand of synthetic oil designed for Seadoo and other PWC/Boats that require an oil that is non-NMMA and non TCW-3 oil (low ash) meets the requirements by Bombardier. In the shop manual, it asks you to use the XP-S oil but if not available, to use an equavilent. So, I too use the Quicksilver. I don't live near a Seadoo Store.......
Johnson.....your oil requirements are to use the Yamalube 2W oil. But, like BRP, you can use an equivalent. For you, the oil must be a TCW-3 oil. That is the only basic requirement for your ski.
My opinion and I think the opinion of many others; choose the oil your going to use and stick with it either until the ski dies or you sale it. Changing oil makers regularly will cause eventual harm, since the motor will be relying on the additives of the oil you use. If you change that oil and it lacks that additive, the engine might not like you for it..........and that woudn't be pretty!:cheers: