I've been running the Dual mechanical timer version for nearly two years now, but I will never buy another one like it. I had both timers quite switching (the timers still spun, but the power switching stopped working) before the first year was up so I took it apart and messed with it a bit. Both timers worked after reassembly. A few months later they quite again. Another disassembly/reassembly and they worked. A few months later the Actinic/moonlight timer quite switching again, but the daylight timer still works, so I use it to run my cooling fan and bought a pair of IceCap digital timers to run my 660 ballasts.