I was told that when Heritage used to make Archtops, they only tap-tuned the one with floating pickups.... so maybe these are tap-tuned.
Personally, I prefer the tone of humbucker archtops.
Vince Lewis told me to my face that floating pickup archtops are fine for "solo jazz", but he said if you are going to be playing with other instruments/musicians then floater archtops are near impossible to use. He said the feedback is awful on floater archtops when you play with a band, their volume is too low, and they won't cut through a mix for solos. I respect Vince's opinions.