Nigel....do you rush out and buy 'new improved daz' as soon as it hits the shelves because its new and improved and so must be 20 times better than the 'new daz' or just plain old 'improved daz' ???
If you do, you'll love this stuff, it'll make your bike smoother, it'll accelerate quicker and make the pillion seat more comfy, plus it'll add an inch to your cock.
If you don't, then it'll make no difference and the plain old 15/40 semi synth that you've been using for years that is already so far over-specced for the boxer twin that anything 'extra' is pointless will do very well.
Hope that clears it up for you