Oil threads are always interesting. We get cranked about what to use. I look for the most economical synthetic oil that has no friction modifiers, and works well. I am using the same oil that I have been using in my Goldwings for the past 5 years - see attached. Bought 10 cases to get the price down, knew I'd use the oil - also use in my car. My '85 and '95 Honda Goldwings were made to an automotive standard and required a good detergent oil that had no friction modifiers - these bikes were also pre-JASO. Have used Rotella T6/T5 and others, but the one I am using now is the best bang for my dollar.
My new to me Spyder requires an oil meeting the API SM or better oil spec with no friction modifiers. There is no mention of JASO - came into being in 1999 - in the owner's manual or the service manual(s). I look for oils that have an API donut that has the oil spec in the upper half and the lower half blank - see attached. Indicates that there are no friction modifiers in the oil so good to go. If JASO is mentioned, it's an indication that there should be no friction modifiers in the oil.
2dogs is correct in that there are only so many plants that produce the oils we use. I was at a Petro-Can refinery years ago and saw the various manufacturers oils on the shelf - Shell/Texaco/Esso and so on. Same base stock, just different additives. Same goes for fuel, appliances, batteries, tires, and the list goes on.
If there is an API donut, make sure the lower half is blank, if no API donut, look for the JASO spec. After this it's cost and availability, and what feels good to you when you ride your bike, specifically when you shift. Some people swear by Rotella, some do not.
As long as you use the proper weight oil, give or take a few numbers, with no friction modifiers, you're good to go.