Larry. He seems so bitter and angry, I think it would be amusing to get him drunk and have him bitch about how much he hates everything the band has ever recorded (seriously, is there any U2 album the guy has ever not crapped all over in interviews?).
Mainly beacuse I'm also a guitarist, and it'd be great to talk influences and guitars and gear, but also because I think it'd be fun to talk to him about the music and experimenting with it, seeing as how it's the Edge's sound that did most of the experimenting.
I would say all of them as they each have different views on various things ie politics, sport, music etc etc so the conversations would at least be varied and what a way to spend your time downing a nice ice cold pint or 2, 3,4 etc............
Id have to say either Larry or Adam. Probably Adam.
Bono would be too political for me. Although it might be interesting it would feel like talking to a politician trying to get you to join his cause....for the first pint anyways. Multiple i might have to reconsider Bono.
Myself knowing nothing about guitars I don't think Edge would be that interesting a conversation, even if he is my favorite band member.
Larry seems like the kind of guy who wouldn't want to be there having a pint. Probably would rather spend his free time at home with his kids
Thus I'm going with Adam. He's kind of an odd ball as is. Would love to hear what he would have to say.