I tried the Ke4Max (bought a 7 and then an 8 iron), and while I hit them well, I didn't care for what I felt was an extremely rounded sole from front to back. In the summer, when the ground gets harder, I felt I had some trouble
getting through the turf. Just my experience, of course, but I eventually sold the two heads to somebody on here.
If I were going to choose between the two right now, I would pick the new STi Gen 2 b/c the sole appears to me to be
more conventional. I notice that the Maltby Playability Factor for the Ke4Max is higher than that of the STi's, but I
would still go with the STi's. JMO.....Others may disagree.....