I hear this is a really good shop / garage heater. My 2-car garage is insulated and I currently use an electric heater and it sucks. On those cold winter days, I freeze my ass off, even with the thing next to me. I was told on good authority (Ginhcreas) that this one is good to go. Reviews are pretty solid as well:
https://www.homedepot.com/p/DuraHeat...2304/100045793