When it's about big touring bikes nothing can beat the Honda GoldWing.
Maybe some BMW tourers came close, but the ultimate benchmark was the Honda.
I must confess that HD is a great marketing success but a poor thing when it comes to riding a bike.
Good vibrations? Rather bad technical solutions. A former M3W owner knows enough about V2 vibrations...
But that is my personal view only and it seems I never understood the advantages of a HD
There are a few well known sayings that rings very true about Harleys...'if I had to explain, you wouldn't understand' and 'things are different on a Harley'. Both Goldwings and BMWs are excellent touring bikes without question.
The V twin in the M3W is not a Harley engine it's an SS engine that IMHO has possibly been used inappropriately or without adequate development in its application in the M3W. Harleys eg don't have problems with rear sprocket breaking up, main oil seals etc.
And for many the Harley V2 vibration/feel is a attribute that many riders want, eg as the engine in the softail models is bolted directly to the frame to accentuate the feel.
Horse for courses
kind regards