I'm slowly replacing mine and just bought a Feit brand bulb for one room and a Cree brand bulb for another. The Feit takes a second to turn on after you flip the switch, and it seems to flicker at times. The Cree is excellent. The Cree bulbs are more expensive, but it's basically a one-time cost because they last so long. Something to think about.
Anyone have any good experiences with the cheaper brands?