polsilver super iridiums are amazing blades. I began using an old-fashioned double-edge safety razor several months ago. I've tested a number of blades. Each brand and model of blade works differently on my face. Of the blades I've tried thus far, the PolSilver Super Iridium is my favorite. It combines sharpness, smoothness, and durability. PolSilver is a Polish brand that was purchased by Gillette. Production of PolSilver blades was moved to a big razor-blade factory in St. Petersburg, Russia, which is a joint venture between Gillette and a Russian company, with Gillette owning the majority of the venture. PolSilver blades are intended for the Polish market, which is why the labeling on the package is in Polish. I've heard that there are other PolSilver blades besides the Super Iridium. I've only tried the Super Iridium.
When I use these blades with pre-shave oil, a good shave cream, and proper technique, I can get a super-smooth super-close shave in less than five minutes total time. I get a much better shave than what I was getting with my Gillette Mach 3 cartridge razor, and at a tiny fraction of the cost. And shaving with a safety razor is a lot more fun and satisfying than is the tiresome act of dragging a modern multi-blade cartridge across one's face.
The downside of the PolSteel Super Iridium blades (and many other double-edge blade brands, for that matter) is the packaging. They come in a tiny paper box with no slot for used blade disposal, and the individual blade wrappers are a bit of a pain to remove. But I now have a blade bank for disposing of used blades, and the unwrapping is but a minor inconvenience.