kixy, great write up! i went rz for dublin 3 and can attest that my experience was pretty much as you described, only i was on edge's side rather than on adam's. i think i got there a little later when the first support act was finishing their performance, got myself a place at the rail and stayed there although there were many people who were sitting on the seats located in the back of the area. if you're doing rz, ideally you'd probably want to get a spot nearer to the front to get a better angle/view of the whole stage. being the third day and with many fans going to multiple shows and perhaps knowing about this, that particular section was more crowded (two, three rows formed from the rail) on the day, so i settled for a place that was basically perpendicular to the centre of the stage, right accross from where larry was. little did i know though that the arched bridge would move to exactly that place a few times during the show, obscuring the view of the stage almost completely. the good thing about it, otoh, is that when the boys came over, you had the best view (as they would often pause on top of it or be walking towards you). in any case, my advice would be to situate yourself towards the front half of the stage for a better view, and if you want to be on the rail as well, be there a little early or when the doors open.
being 5'2 and not up to queueing multiple hours, i saw dublin 1 from a great spot on the stands and went rz for dublin 3. i'm glad i did both as i got both the 'wide shot' and the 'close-ups'. if i can catch another show though, i think i'll definitely try to get a rz ticket.
as for those who are looking to buy rz tickets from other fans, i had to sell mine on the street as i couldn't meet up with the person i was supposed to sell it to. i scribbled 'one rz available' or something on the envelope the tickets were in and as soon as i took it out of my bag when i got to the street corner leading into the gate, i was approached by a shady looking scalper who tried to get it for 20-50. i promptly dismissed him and then, despite my uncertainty, i immdiately got surrouned by quite a few (normal-looking) people. one guy who'd already done rz was interested and i sold it to him for 80 (i'd paid 110). we both forgot about the wristband that comes with rz tickets which you need to wear once in the area, but i managed to find him later, before it became a problem. so, yeah. if you do manage to buy a red zone ticket, MAKE SURE YOU GET THAT WRISTBAND TOO!