I put 444s and monotubes on my bike ('12 FLHTK) back in November, and can only say that it is a different bike altogether.
I specifically went with HD springs since I ride with the wife quite a bit, and when solo I like the extra firmness. That extra stiffness is not for all, to be sure, but it works well for me.
In the land of the night
the ship of the sun
is drawn by the Grateful Dead.
-- Egyptian Book of the Dead
"I found the name of the band in a dictionary one day at Phil's house. I'm wasn't sure what it meant at the time, but as soon as I saw those two words juxtaposed I said to myself "Yeah, that's it!"
-- Jerry Garcia