Stoves are vastly more efficient than open fires (several times so, I
think).

I don't know the stove brand the OP mentioned, but Morso (mentioned by
the previous poster) and Jotul are regarded as top notch.

2 hours seems a very long heat-up time, I'd say it takes 1/2 hour for
me to get a very large woodburner really going (though I use a hot air
gun to initially get it to roar).