Over my life I have had a handful. So far the Kent BK4 is my favorite. I prefer a smaller brush but with a nicely spread pattern of bristles. This one has both supreme softness and a good backbone for lathering. I got it about a month ago and have yet to lose a hair.
I prefer the Kent BK8 over any other brush that I’ve used. It’s great for lathering hard soaps, or creams, and I can’t imagine anything softer.
I also use the Kent BK4, which is just as good, but the size of the BK8 just edges it for me.
However, I try not to keep a brush if I don't think I could use it exclusively, and furthermore, I've sold off a few that I used exclusively for extended periods. I like certain traits in a brush, but familiarity trumps nearly all of them.
So, whatever brush I used, if I used it exclusively, I think I would learn it well enough that I could make it "the one."
Well, I've tried a bunch, and can't seem to get the collection under 4 shelves worth (53) in the medicine cabinet. An interesting question, I read the replies and would second both of these .. but see, there's the problem, I can't seem to pick just one. I like the feel of the Eagle in Pure, but not sure if it would be as interesting every day .. The Colonel is of the all-around category, so I guess he'd be the sole survivor ..