LED Light Bulbs

After comparing prices for light bulbs recently, I decided to go with the LED lights. After all, with claims of lasting 13 years, it would still save money even with the price tag of over $11.
But after installing them two didn't work and the other was considerably dimmer than the professed 40 watt equivalent. I discovered that a friend had also installed LED light bulbs and they didn't work either.
I'd be interested to hear of your experiences with LED lights.