I've been curious about these, are there cheapish ones that can handle 1-2kw power draw?
Does one of your units draw out 1-2 kW, or is that a total usage of our rig? If it's only one unit, you might want to contact an electrician, which should have some proper Watt meter on hand. Otherwise just use standard cheap meters at each connection point, and then add up the usage. That would also make it possible to see the usage of each unit in your rig.