It's more in the shape of the head, the amount offset, and the sole design. I'm pretty picky when it comes to how the toe is shaped (i like mine to be rather square) and i'm also picky when it comes to sole design. I like soles that have a blunted leading edge (to prevent digging because i play in the midwest and we usually have soft grass because it's bent grass), however i don't want the leading edge too rounded either. Also because of the way i swing i a bit more bounce but not too wide of a sole, that requires a nice beveled trailing edge design.
As a for instance, here are irons that i have played and like a lot:
Tech Power Forged CBs (component brand, very similar to the Maxfli Revolutions)
Taylormade RAC LT (original model)
Taylormade TM300 forged
Titleist 775s (slight departure from what i normally play but not a bad iron just too high launch and spin for me even with X100s)
Current set is Adams Idea Pro Forged.
The Adams Idea Pro forged are basically what i want in an iron except i wouldn't mind slightly smaller sole in the short irons. The Adams Idea Pro Forged are almost identical to the TM300 forged, however they are slightly more forgiving and feel better because there is a rubber insert in the cavity (you can't tell unless you touch it which is neat) and they have a better sole design that doesn't dig too much. But like i said, if anything, just a bit too wide of a sole in the short irons.
My list above, minus the 775s, are all very very similar in what i like in an iron. I even had my TP Forged, TM RAC LT, and TM300 forged all together and took a picture...very minor differences.
