Review on TCP 68923DL2 CFL Mini Spring A Lamp - 100W Equivalent (23W) Daylight (5000K) Spiral Light Bulb - 2 pack by Tiffany Scofield

Very disappointing lifespan. Rating "9.1 years" at "3 hours a day". However, I ordered 3 packs of 10 pieces. So count 30 with me: I was supposed to start with 30 bulbs 26: but 4 are broken on arrival (as a bonus I get potential exposure to spilled mercury) 24: and 2 bulbs DOA: no light when put in socket will. 17: 5 bulbs burn out within the first 4 minutes of use. So now I have 17 good bulbs left out of 30 (a little better than 50% survivability). But wait. 9: Another 8 bulbs lasted less than 30 days (more than 25% of total order). I currently have 7 ceiling lights that needed replacing and after only 10 months (ordered November 2015, now September 2016) I only have 4 bulbs left in the box. 4: 5 bulbs died in less than 90 days. Lamps run approximately 7 hours a day (depending on location). The total lifespan is 9,971 hours (presumably the manufacturer estimates its lifespan at 10,000 hours). So my experience is that I've run 20 lightbulbs (excluding blown bulbs and DOA bulbs) 7 hours a day in just 300 days. y use. If we don't count the 7 surviving bulbs, the extinct bulbs already have an average lifespan of 122.5 days † per bulb (assuming nominal usage of 3 hours per day). That's just over 1/3 of a year - just 3.7% of the rated life of 9.1 years. I will not buy this brand again. † (300 days / 2) * (7 hours per day / 3 hours per day) * (7 lights / 20 bulbs) = 122.5 days per bulb