I am going to make a slight revision to my opinion(s) here. It seems that after more & more usage that IMO the Italian Barber Plissoft Noir may just be a tad too stiff for all 'round usage. The softer Maggard's 22mm black synthetic has more splay and just works better for me with a greater variety of soaps/croaps. That's not to say the PN is worse, but just a better match for harder soaps it appears. After careful scrutiny it appears the PN knot is merely bundled more tightly, hence the stiffness. YMMV.
I've been using the Razorock 400 (Plissoft Noir) for the last ten days and my opinion has hardened on the backbone too. Only the Zenith 27mm surpasses it from the dozen or synths I've tried. Absolutely great for pulverising those hard soaps which need it, but an adaption of technique is needed for softer products. In particular for face lathering, painting rather than swirling is pretty much the only way of using it.
Still a very good brush for the price, the fibres and the ergonomics are great, but as you say, not quite an all-rounder due to the density.