The ceiling is often chosen from two photographs: one tidy grid and one perfectly smooth surface. Neither photograph shows the shutoff valve, the low duct, or the junction that somebody will eventually need to find.
Map the things above your head
Before deciding, identify equipment and services needing access. Have the appropriate trades confirm which points must remain accessible and what working space is required. A removable square directly beneath an obstruction is not useful access.
With drywall, draw the access openings before installation and consider where they land in the room. With suspended panels, coordinate the grid, lights, ducts, and panel-removal clearance. Both benefit from a ceiling plan.
Measure the finished low points
Compare finished height below the selected assembly, especially beneath beams and ducts. Neither "drop ceiling" nor "drywall" defines one universal thickness. The construction, installation method, and room requirements determine the result.
Armstrong’s SAHARA product guidance describes removable panels in a suspended system. That is an access feature, not proof that a particular ceiling satisfies your project’s fire or acoustic requirements.
Specify the whole assembly
Have applicable fire separation, sound, height, and permit requirements checked for the intended basement use, especially a separate dwelling. Our preference is removable access where maintenance is likely and a continuous finish where the service plan supports it. The attractive ceiling is the one you can still live with after the first repair.