I was really surprised by my Pelonis personal and portable oil heating unit. Simply by plugging it into the wall and turning up the heat, it was able to drastically change the temperature of my room, providing comfort in the winter months. Needless to say, this device did fairly well, but because of its small size and lack of a true open flame it cannot adequately heat a whole house or very large rooms. This device is best used in small rooms and with people sitting near it, as the heating effect it can create is limited. This also presents a bit of a safety risk, as the outside of the unit becomes very hot to the touch as the oil heats up and circulates. I have burned myself a time or two, but nothing serious just from moving it around or touching it too soon after unplugging. Another consideration is the cost of electricity to heat the rooms you have and how long to run the heater. Consider all of these before relying on one of these great machines.