Sheetrock. It's not that hard for a pro to repair an area or two of Sheetrock if you need to add something later. Just install more recessed lights than you'll think you need and put them on a dimmer, maybe install an electrical sub-panel in the basement somewhere (if your main panel isn't in the basement), plan for a fire place by running a natural gas line somewhere, stub out water for a bar, etc. Try and think every thing that you may want in the basement and then prioritize from there. Also think about if you need to run anything for outside electrical service, like a 220V outlet for camper or hot tub, etc, and it needs to run through the joists to get to a certain part of the house.
With sheetrock you'll also get the benefit of better fire protection for your floor joists/trusses for a few for extra minutes minutes. Drop ceilings offer no fire protection in the eyes of building code.