Fillies are the new ducks. In price, at least.

Max's posts have me jonesing for a "para barbas duras" but I already have a couple of big Fillies, and the prices have risen atrociously.

Can anyone clarify the differences in the different Fillie razors like the one mentioned, the Novodur, Doble Temple, Taurino, etc? In particular, any difference in the steel and/or grind used?