I'm curious about the responses saying that a 22" fits on the FO side.

How? Are there different cockpit configurations that allow a bag to be stored on the FO side? S5's aircraft (physically) don't allow the FO's bag to be stored nearly anywhere on his/her side and some of the aircraft have a silly permanent box anchored to the floor behind the Captain's seat that precludes anything being stored there.

I have put my 22' upright and sitting lengthwise in front of the observer's audio panel behind the FO's seat, but that was only if I was trying to make a quick connect for a commute home and the front closet wasn't an option. This made for a very tight fit since I couldn't slide the seat back very far and an observer would have made it impossible.

How do you guys store them on the FO's side?