I strongly prefer the 24mm bulb depending how density is the knot to allow a better flow through while face lathering.just looking at what specs are preferred for a badger brush for face lathering?
fan or bulb? 24mm v 26mm knot?
40mm+
Stick your head in it and rotate to build lather
Have to say the 24mm High Mountain White fan slightly splayed at the top and set by @TroyTools on the Mink Nebula perfect combination of luxuriously soft white tips, not too dense and a bit of a slap happy painter not a scrubber. Although I do like other knots with a bit of scritch as well but this is my favorite badger ATM.
28mm fan is my favourite.
ThisAnother here for 28mm fan.