>Has anyone had much experience of them? A search of the group archives
>brings up very little yet it seems they've been around for a good >couple of years?
Yup. We have 2 ceiling lights in the hallway, one at each end. Currently have 1 standard 100W bulb in one, and a halogen 70W in the other. Both give identical brightness and colour - really can't tell any difference. Only got the halogen as a trial, but it has lasted longer than the standard bulbs which been replaced twice.