No, all three shave differently, though the IS and Gillette Yellow are pretty close.
Which 3 are the best? What are the criteria? I'd guess perhaps for the average user, in terms of sharpness and smoothness, the Iridium, Gillette Yellow, and some other blade. Personally, I get the best shave from the Bic Platinum.
Right on! glad to see the bic platinum getting some love. my top 3:
1. super iridium
2. Gillette Bleue extra
3. Bic platinum