First off, a brilliant performance
I've heard others play the Elgar piece, but Kanneh-Mason provided the cleanest runs and the best plucks of any I've heard.
He is a player more than a stage performer and he is expert at it.
The only minor complaint I have is, when he played a pre-interval encore, he didn't tell us what it was, assuming, I guess, that an audience comming for a classical performance would know without being told. Which I did not.
Would I recommend spending efforts to see him again? Yes, definitely