Most fireplace glass doors are made of tempered glass with either ceramic or anodized aluminum frames. Glass is placed on the door so that the fire can still be appreciated even with the door closed. Most of these fireplace doors can be bought stock - meaning that most of the door that are for sale can be purchased off the rack and installed with minimal changes.
To assess practicality of the fireplace, we can judge it through its function. Its purpose is same as the classic wood fireplace and so is its function. It produces the same amount of heat as wood powered fire, eliminating the risk of flying sparks, smoke and other risks. These electric units generate no smoke and therefore don't require ventilation. There is no need of getting a chimney built or a duct system.