I'm about 73 mph too. The irons I'm playing hit higher and spin more than anything I can compare to for the past 10-15 years. I'm playing the STi irons (not STi2). Shafts are UST Mamiya iRN R flex. The 7 iron is 31 degrees, 37.5" long. I get the distance of my old 6 iron but a lot more height and spin.
The irons have a nice low CG, per the GW info. I think that is key. I expect the new KE4 Max to be about the same. Irons I'm comparing them to would be like Acer XV Pro, Wishon 752, that sort of basic GI iron. Big difference.
The shafts are counterbalanced, and high launch. Maybe not a good fit for someone who likes a DG profile.
The 6 iron (26.5 degree 5 iron) is playable, but I am liking my 6H better all around. But for a 31 degree club, the 7 iron goes high enough. I notice that I hit higher than a lot of seniors. I don't flip, I take the divot after the ball, but I only have a little shaft lean. I see a lot of guys hitting trap draws that probably worked back in the day, but do not work for a 65-75 mph swing speed.
Lot of rambling. I'm just trying to say there are irons that do help launch and spin at this speed, despite strong lofts. And I think slow swingers should be using more loft. Get that damn ball up in the air!
