My shave with Feather puzzled me. The area between the Adam's apple and the mandible RS-10 shaves without irritation. The left side of the cheek, well, I just can not shave to the state of BBS. Today I got irritated by the overly assiduous pressure of RS-10. And with Blackbird it's the other way around. Shaving the area between the Adam's apple and the lower jaw is getting irritated, especially with the first use of Feather. Shave the left side of the cheek perfectly clean. I still sin on the machine Muehle-41. After the purchase of which I have all the razors should be equal to this ideal machine for clean shaving. But I think this is only an illusion, Muehle-41 for the purity of the BBS will not surpass anything. By the way, no one tried the RS-10 with the blade Voskhod or Polsilver?