For survival situations where weight and bulk are a concern monoculars are a bargain. You don't want to be spending hours looking through a monocular as this is uncomfortable and causes headaches but for general survival uses, like scoping out routes and hazards or orienting yourself to the surroundings, don't require long term observation so a monocular works just fine.

In an ideal world the monocular you get would have fully coated lenses, would be nitrogen filled to prevent internal condensation, would be shock proofed and would be waterproof to a significant depth. We don't live in an ideal world and a cheap but well built monocular might be profitably pressed into service as long as it meets the minimum standards for quality and durability.