Who's got a better sleeper seat: AZ or CO?

[pilot]

My wife and I are flying to Rome in October and getting some sleep on the plane is important. I've flown both Alitalia Magnifica and Continental Business First but in both cases, they were older planes w/o sleeper seat upgrades. If I make the effort to pick out the the right plane, who's seat is better? (Delat would be another option, but they're running about $2K more per seat).