Any big monitor that's too close will be a problem, set up just one monitor properly and improvise outwards with the other two. I use two monitors with one being vertical for coding and the second horizontal for info/manuals/web display and longer processes; my point being that I have one "main" monitor where I do "work" and the other supports that work with less often referenced info.
How do other people in the office use their triple monitor setups? Combine their knowledge with how do you work, what do you spend 80% of your time doing and move them around during a day of work.
Heck, adjust your monitors from week to week - you don't always sit 100% the same way in your chair, you shift around.