.08 per kw is cheap, i could add another light for that, but yeah $60 a month sounds right for 18 hours a day for a light, and yes the digital ballasts are more effiecent and are brighter, they do it by feeding the lamp cleaner, higher frequency power.....or so a local light manufacturer told me, but yeah as far as reliability goes that goes to the core and coil, the guy down at the light shop said he see's 20 year old ballasts come in that dont work and all it is is the cap needs replacing....but here is the flip side, say your new ballast has a 5 year warranty, well in 5 years i think there will be some huge leaps in led technology that those will be the ones to get so it might be time to scrap the ballast all together, but yeah my new quantums will be here in the next few days so for sure ill keep track of them
