I think they have finally "arrived". You can now get them "double ended" which means they work exactly like fluorescents - no need to remove ballast, rewire or change out the "tombstones" (though you CAN bypass the ballast if it dies). To top it off, they are cheap ($10-12 on Amazon, free shipping with Prime), and your local Electric Efficiency agency may well be offering a rebate (if you intend to do this, make sure you get qualifying items - they most likely will require DLC qualificatio). After a trial run I just bought 276 of them. Total cost after rebate = $6.50 ea (plus labor to change out). Total savings = $8.00*/year. Plus, they are brighter than their replacements, AND provide MORE lumens the colder they get, rather than less (benefit in unheated warehouse...). *about 1/3 of that is due to decreased "demand".