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Funny that. I recent bought a few from Morrisons. The only one used so
far has a delay in excess of 2 seconds before it shows any light at all.
By far the worst of all the low energy bulbs I have used since I
switched to low energy a decade or so ago.

A bad batch or bad leccy, perhaps ? I've not had any that have been
that sluggish, although to be fair my own reaction times may be so slow
as to render any delay unnoticeable...

I hope it is not a bad batch as the delay is long enough to be tiresome.
I must try one of the others sometime.

The delay is only when it is cold. Turn it off and on again almost
immediately then it responds promptly.

I have a memory like a sieve but I think I have only had 3 or 4 failures
so far. The failure the bulb in question replaced was a bit curious. It
faded badly and when I went to take it out I actually burnt my hand on
it so there must have been some sort of short.

--
Roger Chapman