No....no.....no. Personally I do not like them, basically you forget about these the battery goes dead and they end up in landfill. It looks as if it has 500ca if in Florida and for about 3 seconds! It is Cold Cranking Amps you are looking for...It weighs in at 17lbs...A proper battery weighs in at 30+Lbs and does not have jumper cables, compressor, weight...Just power to start.
I have come back to cars at night at -35 and just got them to start...I have learned. An air compressor will not help in this situation. This would be like hooking up a motorcycle battery to give you that extra.
Diesel = cycle glow plugs 3 times 60+ amps for 15 seconds, fire the starter 200+ amps, keep glow plugs cycling for a few minutes till combustion chambers hot enough to keep running.
If you want a second battery add a second battery with an isolator (jay does really clean installs of these).... A proper second battery will be charged by the alternator and used by the vehicle giving you long life and battery with value to recyclers.
Make sure you run synthetic oil, good glows, and well tuned and the diesel should fire every time...
If you are leaving it for a long time I would add a disconnect switch on the battery to disconnect it so that power does not get bleed off from few things with ghost power (radio, clock etc)...
How cold are you leaving it and how long??? Interior -30 or lower then it might be time to invest in a littler generator to power a block heater, oil heater, and battery warmer (in the old days they just made a small fire and pushed the vehicle oil pan over it

).