In reply to Neil Williams:
FWIW, my house is now 100% LED GU10 spots, the tenner-a-go Philips ones which provide an excellent light quality and no discernible flicker.
I suspect I have low persistence of vision, though, as I find almost all cheap ones have a visible flicker. Same with all car tail light ones I've seen, they are really irritating.
The latest annoyance is that the decent independent cafe outside Euston station on the left has installed daylight-temperature cheapo LED spotlights, which fail on both counts and may well put me off going there in future.
Neil