I switched from mizuno blades in nov last year, its been a revelation for me, it gives far more confidence hitting 7 iron the distance I used to hit a 5, phylogically at least though there are more or less the same loft. I had MP4 before and hit them well, but the jpx go high and straight. Like today, didn't hit a good drive on 12, had 195 to the pin, 6 iron pin high, I would have struggled to hit the 4 iron that well to get there. Though I was sceptical to start with, the proof is in the pudding, for me anyway.