I currently carry the MP-62 irons which I love. Unbelievable feel and they are forgiving, but not too forgiving at the risk of losing quality feedback or playability. I've hit the Miura irons and I thought the feel was about the same as the Mizuno, but at a much higher price. And as an update, I got to hit the new Adams MB blade irons, which had a nice feel. However, that was the first time I had hit the coveted KBS Tour steel shafts and I thought they were a bit too light for my tastes.
Here's the latest prototypes that Mizuno had out at Wentworth not too long ago. Special thanks to GolfWRX.com for the photos. These would probably replace the MP-67 blades.