The Mozo communicty has rated Sumo Power products and services on different specifications ranging from pricing and bill clarity to customer satisfaction and green energy.
I like Sumo because they are an Australian company with a local call centre. Although they don't have the absolute lowest prices, they are pretty close to the cheapest. Any time I had a problem with the bill, their call centre agent was able to sort it out quickly.
Have only changed to them in recent times as was unhappy with the cost of electricity with previous supplier. They appear to be marginally cheaper.
They rang me and said they could do better when I wanted to change so any saving is good saving.