Agree with Don, the only tough part is they are super low balance point so if you are going over length swingweights will be high. I play the UT 105 TX in my driving iron (its really just a 2 iron blank) and i struggled to get it to D4 at std 3 iron length in my u500 3i.
Overall they feel really good super stable and the first graphite iron/hybrid shaft that I feel I can actually hit down on.
Just ordered another one to go into something special in a couple weeks.