Block heater suggestion.

Need a suggestion on a block heater on my new truck. I'm looking at 2 options:

1. Espar tandem (diesel fired) coolant and bunk heaters. Coolant heater has circulating pump.

2. Small APU with ability to charge truck batteries through inverter, very powerful (13.500btu) bunk heater and ability to power my truck factory electrical block (immersion) and oil pan heaters (on the same plug).

Now, I know the diesel fired coolant heater is more powerful then the factory electric one, plus it will circulate the coolant. However the factory setup has also the oil pan heater that is wired to the same plug with block heater.

I'm just wandering if factory setup with my APU would be enough for northern Alberta winter temperatures. Need that truck up and running every morning.