Picked up three cheap (£5 each) in the closing days of BHS in Kingston,
even though I am skeptical about actual ratings vs 10% allowances,
these seem to give similar light output to other 300lm+ GU10s,
ie very improved efficiency over the older lamps,
with a warm and pleasant colour.
<p>
In our kitchen I have replaced 7W lamps with these with little apparent loss
of illumination, bringing each of the two strings down to 20W as of 2016/08,
for maybe 18kWh/y saved (3 lamps x 3W savings per lamp x 2000h/y on-time).
That would be ~1% of our gross electricity consumption,
largely when local microgeneration from solar PV is not available to supply it,
thus reducing imports from the grid more as a proportion.
<p>
2022-07-01: one lamp failed flickering fast and annoyingly.  Seemed hot.
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