I found out about the additive package a very unique way. I also belong to a forum called "The Motor Oil Site". One of the members submitted a paper on oils and the Harley Davidson, comparing quite a few of the oils that could be considered for use beside Harley's branded oil. He lists additive levels, TBN, cST specs at operating temperature, aging, and volatility levels of the different oils. Maxima Extra topped the charts in the additive department, with no moly for the clutch packs. Ultra, according to Danny at Maxima, said that it is just like an "improved" version of the Extra, so that's whay I went with it.
Now does this mean that it was the top of every list...no. A product by Pure Power, topped the TBN chart at over 17. Most moly, of course, went to Redline (no big surprise, as their levels of moly are discussed very frequently). But the cST and stability levels, along with the rest of the additive structure sold me on the Maxima. So much so that I even use it in my car. As someone stated to me, what has API done for me, I replied besides lower the additive package content so that emission parts can last longer...nothing. My vehicle doesn't use a drop of oil, so the whole CAT poisoning issue is a non-issue for me.
TBN is important, but it isn't everything, particularly in ATV's and such. Oil is usually changed based on hours, not miles, and due to the very nature of just how much a lubricant is torn to shreds in a shared case system, TBN really isn't depleted long before the rest of the additive package is well used up. Most of the ATV and bike oils will have a higher TBN to start with, so you'll be OK in the neutralization department of those nasty acid formations.
4 ball wear test - great on paper, good marketing tool...not really all that important in the real world situation of an internal combustion engine. Amsoil makes a great product line as well. I have used them in the past, as my friend is a distributor, and besides him and his family, I'm is only other customer. In fact, I still use their oil filters, now that they came out with the EaO line. They are top dog in my book, and can go longer than any other filter IMHO.
Bottom line is, if you see something about an oil that you like, check it out as much as you can, then decide if you want to use it. Even though I use Maxima right now, I constantly search for better, newer, technologically different, and just plain change of brands time, so I could be using something different next year. In fact, I'm checking on a couple different ones right now, as my other posts are asking about GReddy oils (from Japan), XADO oils (from the Ukraine), and on another forum, I'm asking about Aerospace Lubricants' Alysin ProGrade 21 0w20 formulation.
I like to tinker, try, sniff, feel, look at, and enjoy reading about and using all kinds of different lubricants...my wife seems to think that I'm obsessed.....NAAAAAAH!!