creating drop zones

I am making a title shoot and am new to Motion. I have 15 seconds where I need to have 4 vertical panels completing filling the screen. Each panel will change video material every 2 seconds. I understand how to use key frames to change the panels but am not certain about ensuring that each panel is equal is size. I am also concerned about minimizing distortion as I scale down the drop panels. Any suggestions as to best way to do this project?

A dropzone can only have one object placed inside it, so I don't think that's the way you want to go - what you describe is easy enough to do directly in FCP by scaling and/or cropping, I would just do it there.

I tried scaling and cropping in FCP but had a hard time making each panel equal in size. Do you know of ways I can mark the canvas or make sure each panel is equal in size?

Scale and crop one - then duplicate it and replace the media with paste attributes. Repeat.

I actually wound up using masks as the allowed less distortion of video shots but was given the wrong information for length of project. It has now been changed to a 4.14 minute music video with the 4 panel screen changing about every 2 or 3 seconds. We are following the beat of an Irish drum. Would you still suggest following the same method in FCP?