Situation: when you open various files in FA2 by right-clicking in Explorer, opening all in the same instance might be useful.

Experienced: 2 files would open two instances.

Expected: all in one window now that we do have MDI.

Drawback: fou might want to cemapare different groups of files. In this case, you could always manually open a new FA2 instance and open them there through the File Open dialog.