Which 99 will be faster?

i'd have to say cooking. without no-lifeing it, my friend was able to get 75-99 in like 2 weeks

 

Fletching, unless you buy a better fish and get more xp with it.

And I agree with Qq Bloody Qq. Get a better 99. Hunter almost takes as long as fletching.

 

Fletching is boring and hurts your hands, I'd rather just do cooking, I have around 80 fletching and almost 98 cooking (Didn't train it in a long time) but cooking is funner, and if you cook at the rogue den, you can talk with people, beats fletching.