I read somewhere, that the dye is either poisonous or carcinogenic (sorry, no source, I have to search for it again). So I am not sure if putting it in the microwave is the best idea.

I would avoid the userbenchmark site, the owners are heavily biased against AMD, so their benchmarks cannot be trusted

What’s the average price during normal times? In Germany we are usually paying a fixed price, so fluctuations on the market do not reach the customers. However, this price is somewhere between 30 and 40c/kWh.