Review on Sunlite PL13 SP65K 10PK Fluorescent by Amy Fuhrman

I bought this pack to replace fluorescent lights I bought a few years ago. A few weeks after installation they still make annoying "ping" noises for a while after I turn them on. I don't recall this happening to the original batch. The first batch didn't last as long as advertised, but I suspect that's because I use them for my bathroom lights, which flick on and off frequently. They would probably last longer if I left them on; but that will waste power.