Well, I was lucky to attend a fine bunch of gigs of the tours you mentioned: in different towns, on various continents. But for every tour there is one general rule: You can feel more intimate, more closer to the band. This is only possible, when you "invest" (nearly) the whole concert day in preparing, meeting friends and queuing in front of the arenas/ stadiums – and you are able to be in the front section, close to the stage(s). This phenomenon is well known for the last tow tours, but it also was a fact during POPmart. When you were up front in the barrier cage, you could watch the moves, look at the faces' expressions, judge, whether now there were moments of anger, routine or pure fun. And you are circled by fans, who want to do the same – a lot of them unfortunately seeing it only as a big party now with more concentrating on their handy functions, calling each other during songs or heavy drinking beer and chatting loudly even during acoustic songs. Sometimes a kind of sad picture, that makes you feel nostalgic to the more 'holy' atmosphere these U2 concerts had, when there was more attention to what was going on on stage. Real intimacy now you only get on rare nights, when the crowd is right, behaves right, sings along as 'one' and the band rides this wave ...
Another negative point is: The closer you are to the stages, the more you lose he momentum of the (in all three cases) spectacular stage designs and effects. This 'whole picture'-view (with the band members much more far away) you can only get froom good seats, where you were higher than the ground crowd. I had the possibility on all three tours to enjoy this view, and it was very worth it, too. There you recognize effects and details, the get together of lights, screens, music and stage performance, that you lose up front. But you may have bad luck and might get disturbed by misbehaving fans, too, that might disturb your atmosphere. So you decide, where you want to go. It's not true over all, that 'only up front' is the place to be. And by the way: Guys, that come late, and think they are very clever to push forward to get to spaces, other fans do have, who have waited for ten hours or more, is pure aggression – something I don't understand at all for people, who claim to be fans of U2's music, lyrics and values ...