I've revisited both the Iridium and the 7o'clock Yellow in recent weeks with technique improved over my previous attempts last year.
Last year I had serious irritation issues with the Iridium, and found the 7o'clock yellow smoother.
This year, first of all, I've noticed that the Iridium is PTFE coated, and the 7o'clock is not. The Iridium seemed smoother, but both blades are so sharp that I found a slip or two in technique resulted in weepers and nicks that I don't get with more forgiving blades, like the Shark and the Treet Durasharp Classic.
I've also found the glue spots on the Iridium and on the 7o'clock off-putting. They're large on the Iridium, and encroach on the grind part of the edge. They also left residue on the underside of the doors of the Schick Krona I was using.
I will use the Iridiums and 7o'clock yellows that I have, but won't be buying more.
Wonderful blades. Smooth -- almost as if the blade is not on your face. Easily lasts one week at a great price. Stock up while available. The banned vendor provides excellent customer service.
Derbys and Astras are not even close to the Iridiums.
The Iridiums are not as sharp as Feathers. Difficult to determine if Feathers provide a better shave. Iridiums may are smoother and more forgiving than Feathers though.