Do Propane Heaters Work - Are They Safe for the Garage?

I've been putting off buying one of these for a long time because I was wondering if they are safe or not. In this video, I share my thoughts on whether or not they work well, and how safe are they.
Links where you can buy similar items on Amazon:
Garage Propane Heaters:
First Alert Combination Explosive Gas and Carbon Monoxide Alarm:

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