I have just read the reviews for many electric jugs. In my opinion all are substandard at retaining the heat in the water.
The amount of power used can be halved if they insulated the jug. This would make them quieter as well.
The standards set by the reviewers is below standard, That is the amount of electricity to boil one liter of water is always going to be the same what differs is the amount of heat lost during and after the process.
As it stands now stainless steel is out as the amount of heat lost is unacceptable to the point of being dangerous to touch them. Plastic is much more efficient but they all could do much better.
We as consumers need to expect and set higher standards for all goods.