Question about the U2 360 Tour stage...?

My dad is a big fan of theirs and he's never seen them, so I was thinking if I had the money for Father's Day I'd get him two tickets, so him and his girlfriend could go. My question is, am I better off getting the seats in the back of the stage off to the left or right thirty rows off the floor, or the seats on the top level of the stadium in the back or middle, both top level sections with seats left are in front of the stage? Depending on the money situation is what decides if he'd be on top in the back right corner, or on top in the middle, the middle top is the same price as the back of the stage seats thirty rows off the floor. I hope I wasn't too confusing. Thanks in advance.