I know that the G1000 is not approved for II, III, IIIc ops, but I reckon in an emergency where you have no other option you could do a zero/zero landing with synthetic vision and walk away.
Would be interesting to know if people have actually done this. Of course with a second licensed pilot on the right seat. Is it really possible to land e.g. a Cessna 172 until full stop with just G1000 synthetic vision?