After reading Steve's endorsement of his In1Zone driver some time ago (though I doubt it is still in his bag), I decided to track a head down for my 83-year-old dad who has been really struggling off the tee. I bought a 14* head from Rickochet, shafted it up on an older Graffalloy shaft that I had in my inventory (a 56 gram Launch Apex 145 HT). I then took dad to the range to hit balls with a split grip before cutting the club to length. His optimum length with it turned out to be 43".
Man, does he like that driver! He has gone from hitting consistent over the top pull hooks to hitting the majority of his drives in the fairway and quite a bit longer than the 10.5 TM he was hitting (which I'm sure is due to the more appropriate loft). I hit a few drives with the In1Zone on the range and, while the loft was too high for me, the contact felt great and I hit the ball dead straight down my line with it. I own a 1IronGolf "SL driver" and played with it in the past, but I found it really "tinny." That's not the case with In1Zone. I'm thinking that I may even order a 10.5 and try one myself. The only thing stopping me is that I'm hitting my current driver really well (a Wishon 949MC).