I've just fitted my first one of these in a down-lighter at home, bought from my friendly independent light shop and it really is the business! Bright light straight away, only 4.5w so really energy efficient, but....and it's a big BUT for me...£16!!!
Now I really would like to support a local business, but I know they're not struggling - they've expanded the shop in the last year and sell online - and given that I've got a dozen down-lighters in the kitchen, and about a dozen GU10 lights elsewhere, this could get rather expensive! I don't need to replace every bulb now (most of them are of the spiral fluoro type, so already energy-efficient of sorts) but I'm looking for recommendations of cheaper sources. Are ebay ones any good? I've seen some on there for £22 for a pack of 10 from a Uk based shop - a very significant saving compared to my purchase - but do you get what you pay for??