Had a Can-style Propane, unless you have a big propane tank it's not worth it. I had a 30# but would eat through that crazy quick. It was quiet though, but was a hot surface all the time, and i melted a few things on it
Torpedo, I currently have 2, one is 25+ years old and after changing spark plug and all the air lines it is back to perfection, also have a newer one. purchased last year.
The new one is a 55K/70k btu (has a hi low switch). Runs on kerosene or diesel, almost no smell. I can put it on high and get my 2 car uninsulated garage from 20º to 70º rather quickly. I can run it for a bit and work in a t-shirt.
Will usually run it for like 20 minutes before i go out there, and then go out and when it's t-shirt warm i'll turn it off, and then i can pretty much cycle it like 20 minutes on 30 minutes off or so and stay nice and toasty.