1/2 club more distance (roughly) per club and slightly lower ball flight. That has been my experience with my change from 714AP2s to the 2019 T100s irons. I can't speak for the 2021 T100s irons although allegedly they are faster with higher ball flight. Not sure it is materially different than 2019 however. Probably more aesthetics in the end for the average player.

I have the 2021 T100s and for me the differences are better turf interaction, higher ball flight and more distance. I also think they feel a little better. The biggest change is i think the T100s irons are the best looking I have ever seen

I went from 620CB to 2021 T100s. My 620s were a degree weak. The T100s were 3 degrees stronger in loft from my 620s, but I am a club longer, which is probably expected but ball flight is considerably higher with T100s. So happy with the T100s. Look clean, and work well for me.

I just recently picked up the 2021 T100s and have only played one round so far. I had the 2019 T100 and while I liked them the AMT White shafts were not my favorite. Moving back to a project X shaft for me is an improvement.

One thing I did notice during the round was the turf interaction is much better with the T100s. I have always played my irons 1-2 deg strong since I have a high ball flight so I will have to see about the distance. Since my round was during a windy day it's hard to say but the ball felt like it popped off the face and I am looking forward to seeing how they perform as I break them in.