Depends on you just use it for load only, or you ever going to run distortion analyzing (THD testing). I had experience buying those high wattage non inductive resistors that is non linear and cause THD measurement to be wrong.
Also, do not trust some of those metal panel mount 8ohm 100W or so resistor from ebay. I ordered a few, they are small, like less than 3" long only and very narrow. I complained to the seller and he kept saying it's right. The size is so much smaller than a real Dale 100W resistor. From my experience in the field, it's no more than 25W size. So if you buy from those place, don't count on their claim.
I read before people use those water heater elements you can get in kitchen house hold store. I have no experience, those might be cheaper. Take your meter to the store and measure the resistance!!! I'll let people that try this to give you more info.
