I've lived in The Gap for 25 years with the base of Mt Cootha right at the end of my street and we've never had an issue. Having said that, you must realise that where there is bushland, there is the POTENTIAL for fire. Just keep that in mind and chose your street carefully (obviously, those houses right up in the thick of the bushland are going to be more at risk).
We've lived in The Gap for the past 3 years now and it's never effected us. We're at the base of Mt. Cootha too. If you're worried about fires, just look into the areas of The Gap not surrounded by bushland.
I have lived in the gap for 9 years and whilst there have been some near misses for those houses that are up against the edge of the surrounding bushland, I am not aware of any loss of houses. If this is a concern, then I would look for a street that isn't close to the bush and you should be ok.