I have the fanatic and old incinerator. I think they are equally as warm with the fanatic being quieter but a touch more bulky than the incinerator. The new incinerator will be even less bulky. If there is rain/wet snow and wind I'll be in the incinerator, any other time I prefer the fanatic.
If i could only have one set it would be the fanatic due to the quietness and overall pocket layout.