Dane Spearing wrote:
ii) VFR and hand-held GPS systems are not authorized for IFR
navigation, for instrument approaches, or as a principle
instrument flight references. During IFR operations, they
may be considered only an aid to situational awareness.

Hmm. I couldn't stand reading through the whole Advisory Circular, but
as far as I can tell, the paragraph I above is the opinion of whomever
wrote the written test prep. AC 20-130A seems to only give
requirements for obtaining IFR approval for a panel mount system and
give criteria for when the "VFR Only" sticker must be applied. But
does it even say what "VFR Only" means operationally? It doesn't
mention handheld GPS at all (AFAIK).