I have Ken Light's machine. It is not a good option for a guy that needs to anneal 100 cases, 5 totally different sized calibers (i.e. none based on or close to each other in case size) twice a year. But if are doing any type of rifle match shooting where you shoot 300+ rounds a month it will certainly be well worth it.
For those that don't know what we are talking about, Ken Light makes an annealing machine the consist's of a rotating disk that the cartridges set in, and while the disk revolves, the cases spin as well. (Think of Earth's orbit) as they spin on one side of the machine are two propane torch holders that you mount and adjust however you need them to properly anneal the case you are working with. Great machine, quality you don't expect, but they are not cheap. I think around 300 for the machine with one disk, and an extra 50-75 for the extra disks. Each case head takes a different disk.