Good, but not sharp enough
I used the Merkur Super blades for awhile, and they were OK, but they don't compare well to Feather blades. The Feathers are sharper allowing for a closer shave with less irritation.

I decided to give these 4 stars because I haven't found anything that beats them other than the Feather.

a must for your merkur razor, sharp and to the point shaving
not much to be said other than you need these for your merkur razor. These are very sharp, and will give you an amazing shave. If you are new to merkur double edge razors, start slow, and with short strokes; shave with the grain of your face. Switch to other side of the blade after each pass, and rinse in hot water, and then do again. You will become a shaving pro in no time, and wonder how you shaved your whole life without these. Keep your extra blades packed in their original box, and outside the bathroom, such as in a closet until you need to use them.

Best blades for a Merkur razor
If you have ever thought about using a safety razor, you are on the right track. I have tried every type of razor out there: disposable, electric, Mach V, whatever. Every one of them has always cut my skin, left razor burn, and my skin has bumps.

This Christmas, my wife bought my Proraso, Merkur safety razor, and these blades after doing her search and I have to say I will never go back. This is the best way to shave out there. Its not as convenient as the disposable blades, but your skin will thank you. I have had zero razor burn or skin bumps since December so bye bye any cheap alternatives for me.