Dorco and Merkur.
I'm kind of surprised to see Merkur listed as a bad blade by some. I've had success with them thus far and can usually stretch 10 shaves out of one blade.
I am baffled by all the Derby Extra comments. I purchased hundreds of them 5 or so years ago. They are absolutely excellent blades, Quality control in recent years, maybe?
One blade I remember as being horrible is the Laser made in India.