cracks: yes true.

safety: solid wood

durability: if installed inside the house will be pretty much the same unless you abuse the door or keep it in a very moist environment. then solid will last longer (but look crappy just as well)

price: good moulded door will be slightly cheaper than a regular solid door. but not much.

for inside i would always buy moulded doors (with full filling for sound proofing) instead of solid. have both types (kitchen is solid with glas couldnt get the design we wanted as moulded) and they are all OK but the solid one shows some small cracks at the joints due to the aircon environment.