I like a lot my BK8. It has 25 mm knot and 55 mm loft. I don't have BK4 but I've read it has a little more hair than the latter. It's NOT floppy and has wonderfull water retention and flow through. It's extremely efficient with cream and soap for bowl lathering. It feels big and luxurious on the face but not too soft as some people describe it. The biggest strength is the springy and resilient fine hairs which don't feel splaying too much despite the knot size and not too great density. The handle feels exotic.
I always think about this Kent brush as a Simpsons' Best hair knot on steroids.
Last edited by edgerunner; 03-10-2012 at 12:11 PM.
-= Boris =- What's your memories worth, if no one is around whom you can share them with!?