I have one (They are called Autoterm now) and it has worked well. I have had one issue but that was resolved with a free replacement. They have a 3 year guarantee. There is excellent support and advice from their Facebook group page. They only need to be run once a month for 30 minutes when not in use. The Comfort controller (human interface device) is excellent, runs up to 3 programs a day and can run in thermostat mode, will remind you when you need to run it.
highly recommended. Much, much quieter than the Alde heater that it replaced