I'm a happy user of the Econo-heat, a wall-mounted convection heater that silently keeps the chill of a cold room. New for this winter is the Envi heater, which appears to be based on the old Econo-heat model, which is still available, but addresses several concerns.
As you can read in Convection Wall Heater, the Econo-heat seems to eventually, inevitably, crack. This doesn't seem to impact the way it works--one of mine is cracked with no ill-effect--but it is an aesthetic problem and causes anxiety for some customers. The new Envi seems to address this by using a new mounting system, which is thought to be the cause of the previous cracking. But it also encases the heating panel so that if cracks develop, you'll be none the wiser. Clever. The new case is also more stylish and adds status lights and other nice touches. Learn more at the Envi website.