I’ve personally been very skeptical of the claims of companies that sell flourescent bulbs. The cheap bulbs that are 99cents a package (of four), and sometimes go on sale for 69cents seem just as long-lasting to me. Even at regular price (25 cents per bulb), it would take 20 of them to match the $5 (or higher) price tag on many of these supposedly ‘economical’ bulbs.
Our overall experience, using several different brands from several different sources over several years has indicated that these are not longer lasting and although I haven’t done any scientific testing. (I only buy them if they are steeply discounted). I have not seen any substantial difference in our electric usage.
I am posting this today because we just moved into a new house, and installed two of these bulbs (they were a gift) into a living room light that is difficult to get to. Today is our 15th day in the house and one of the bulbs just went out. If a cheap 25cent bulb went out after two weeks, I would be disappointed, but not feel like I just lost $5!