Mileage does vary. So very true when it comes to blades. Derby Extra works fine for me. Personna Med Prep works for me too. But Feather doesn't for some reason.
I'd try these new (or repackaged?) Derbys if I knew where they were available cheaply in the US.
I'd try these new (or repackaged?) Derbys if I knew where they were available cheaply in the US.