I'm considerating this but what difference in these have any of u guys noticed?
I have a 23mm 177. The loft is long (almost 60mm) which makes a brush with very few backbone and massage feeling on the face.
It is a great bowl latherer with good flow through but almost impossible to face lather with (YMMV).
This put aside, a wonderful hair, very well made knot and a very soft feel on the face.
If you want something more versatile, ask Bernd at Shavemac for a custom made brush with a shorter loft. His D01 is more expensive and his finest the best deal unless you look for the silver tip softness.