Supposedly, Merkur blades are better made than Sensor blades or Mach III blades or [insert your Gillette or Schick razor blade here], and hold their edge for a longer period of time. They are also much cheaper. Also, there is no plastic involved, so they are environmentally friendly (to the extent you care about this). I am a Merkur user. The main reason I use it has less to do with blade quality and more to do with the fact that double and triple blades irritate my face and cause ingrown hairs. The Merkur does not. Of course, YMMV.