I got started on Kolinsky brushes with W&N Series 7s and fell in love with those. Since then, due to their cost and difficulty to find in Canada, I tried many other Kolinsky sable brushes and never found a truly comparable brand, until Raphael 8404.
A number of years ago, I heard there were quality control issues (W&N suffered from this too sometimes), and that paused my trial of these. Present day, I am in need of brushes again, tried other brands, but I need something that I experienced with my first Series 7s. Raphaels are basically nonexistent in Canada, but I was fortunate to find them here.
After a couple weeks, now they still brush like butter, no curling, water retention is excellent, maintained point, and the brush length is perfect. Everything I want in a brush and what I remember from my first experience with a Kolinsky Sable brush. I got sizes 0 and 1, highly recommended.