In our bathroom we have a grid of 9 36 W halogen bulbs. I just replaced two of them with 6 W LEDs. Would it make sense to replace the rest of them for the energy savings (7*30 W, lights are on maybe 2-3 hours per day on average, so ~525 Wh per day), or is it better to use the existing ones until they die (taking into account the manufacturing of the replacements)?