I'd order Yamalube and stick with it, since you're not changing the oil in your four stroke all that much. I rarely get excited about manufacturer's saying to use only their products with their products, but I tend to follow it on marine lube.

Additionally, I would want to cover my bases in the event of a warranty repair or factory recall. I have heard of warranties being voided because the owner used products that differ from the manufacturer's recommendation. I think, though, that's no longer an issue. I'm going off of distant memory, but one of the big guys got in trouble with voiding warranties on engines due to different brand lubes, but they had to honor the warranty as long as the owner was using a lube that met NMMA(?) specs. As long as the lube is in spec, the warranty can't be voided. I think.

It was explained to me once that it's best to choose one brand and stick with it when it comes to two-stroke motors, especially oil-injected ones. Apparently, mixing brands could lead to some gumming issues and separation because different brands will have different weights and mixed detergents and such. I have no idea if this is true, but I have followed the adage and seem to have fewer problems with oil and such (knock on wood) than others. Even though my current motor (Merc) is pre-mix only, I still make sure to use Quicksilver lube in the gearcase and gas tank.