Highly rated wall heaters include the Econo-Heat 0603 and Cadet CEC163TW, according to reviews on Air & Water. Each model has at least a four star rating on Amazon.com, with generally positive reviews.
The Econo-Heat 0603 is an inexpensive, efficient, sleekly designed wall heater for safe use in homes. Reviews on Amazon.com are mostly positive, but complaints include poor quality material and potential melting at the connector from prolonged use.
The Cadet CEC163TW is a highly efficient in-wall heater with intelligent programmable controls. Consumer complaints include hairline cracks and internal faults out of the box. Both companies offer easy installation guides and troubleshooting support.