I've looked at the DD myself but thinking more for the shoulder seasons. I don't know anything about that heater and i would research that carefully. . I would be more comfortable with a small wood heater. You will get condensation with the DD when its cold out that you won't get with canvas. Many yrs ago i use to heat my nylon tent with a propane light . It worked for short periods of time but i do recall condensation.
" The mind creates the abyss, the heart crosses it."
“The measure of your life will not be in what you accumulate, but in what you give away.” ~Wayne Dyer