I got one of these for £45 a couple of months ago so thought I'd post an update. I wasn't sure I'd like it after my first couple of shaves, the bristles were very stiff and the knot being so dense made it quite difficult to shave with.
Happily after a few weeks of use it's softened up a fair bit and I'm finding it much easier to use. I only use synthetic knots and have owned a ton of different ones, the Simpson knot is unlike any other. This knot is so dense it feels totally different to any other synthetic I've come across, even compared to stuff like the Synbad they're nowhere near as dense. Overall I'm very happy with it for £45.