Not a fan of the 5000k just seems to not be so good, the 4100k are doing better surprisingly. Every ballast produces a decent amount of heat and thats why most every ballast is up high in commercial grows to keep the heat above the plants. LED however, put out more heat then the driver. You should jump on ebay and search "LED Chip + driver" you might get interested really fast in what comes up. I am already looking for parts to build my furnace. I know how to make custom heat sinks so I am going to be building my own 30k lumen led panels.