I have had a chance to try different irons Muzuno blades/muscle back, Ping G5 and Tour Edge Exotics irons. All have shiny soles but are progressively larger for more game improvement. The 4 iron sole width was Muzuno 3/4 inch, G5 1 inch and Exotics 1 1/4 inch. All clubs had similair offset. With both the P3pro and the DD I found the Muzuno's to give the best accuracy. This is subjective but based on how well I felt I hit the ball and where on the screen the ball went compared to what the sim showed. Also based on how well I was able to try and hit a draw/hook/fade and slice. Just as you would expect the more narrow clubs seemed to register more accurate and consistent with both the p3pro and dd. I also compared the clubhead speed to the vector clubhead speed but found all clubs to be comparable.

Conclusion: Blades/muscle back clubs may be more accurate than wider soled game inprovement irons. Obviously this is subjective but justed wanted to throw this out there.