I bought a batch of these because I wanted to try the sensor style blades in my headblade (just bought the sensor headblade adaptor...been an atra blade guy since I started shaving my head).
The blades that are part of the deal could be the worst blades I have ever tried! I'm fortunate I did not hack up my head. I actually thought I had the blade in backwards.
Guess you get what you pay for.