I saw two of them: Bucharest and Slane.
I have to agree with something I read here on IORR a few weeks ago, that the band was at top speed during July, in the middle of the tour.
Watching a lot of concert movies on youtube and comparing various shows in various moments of the tour I will say that Bucharest was one of the best shows in the tour ( regardless the fact that it had only 18 songs ).
Keith was not in top physical form in Bucharest, struggling to keep up in 40 degrees celsius, but he played excellent, including a fancy and delicious Brown Sugar intro
Add to that a very good venue in Bucharest ( old football/athletic stadium, wide opened, with beautiful sound, no echo at all ) and a superb crowd ( more than 60 000 , hot and cheerful.
From the band's total energy and tempo, I may say Slane Castle was a little bit lower. But there we had a beautiful location and a very special event to remember, a lot more than a regular show.
Keith was a lot better, head up, very good performance. For sure the best You Got The Silver in the whole summer ( I may say I compared YGTS from most of the shows ).
If you were just a bird sitting in the far up corner of the concert venue, my guess is that everybody's choice would be Bucharest, Belgrade and Slane, each of them for different reasons.