Originally designed for use by barbers. These are the sharpest and most durable blades on the market. Every day there are more razors that use them. Starting with the Cobra, then the Mongoose, Above The Tie SE-1 & SE-2, Colonial Razors' The General, RazoRock Hawk, and iKon MR-SE (El Jefe), with more forthcoming. They are thicker, stiffer, sharper, and longer lasting than DE blades. They could be the blade of the future.

Very sharp. In fact the sharpest.

Very long lived. Over 10 shaves per blade is not uncommon.

First two shaves are often rough. After that it's smooth sailing.
I palm strop mine, to eliminate that problem.

At the time of this writing, they can be had online for as little as $10.99 for 20.
Considering their durability and sharpness, that's a very good value.

Top quality.

Sturdy and safe packaging.