Just did a downwinder, wind dropped out but there was knee to hip high chop.
Me and a mate paddled the New Red Fanatic 14ft and 12'6.
Paddled the 14fter first while my mate paddled the 12"6, we then swapped half way.
I found the 14fter to be an easy stable board.
caught chop easy and was allround nice.
then i jumped on the 12"6.
much less stable but hell it bolted in the chop.
rolled a little when planning on runners but overall it was quicker.
We both where convinced the 14fter would be faster but know we arn't so sure.
unless your paddling the oahu-molokai everyday i think the 12"6 would be a better allrounder, even in down winders.
thats my 2 cents anyway.
enjoy
nice wetsuit there scuba steve.
I have a action man doll at home that looks like you. hahah, prey for a big downwinder sunday
I thought that seal suites and red boards wouldn't be a good choice in Great White country 
I'm loving the 14ft at the moment though.
I have a 14 footer and weigh 101 kg found it better in the open water for my weight
and I would like to add it is also BETTER than my old 14 glide speed and ease of pick up swell IM in love with my big red one
Had a paddle on the 14ft Red Fanatic prototype (Carbon model) on Saturday. Great in flat water and I reckon would blitz on a downwinder. It is only 27 odd inches wide and therefore much less stable than the old white 12.6 by 31 model. I'm 98 kg and would say that it almost had too much float for me. We racing a rectangular course to 2 sidewind legs, one down wind and one up wind leg. Within 5 good paddles on both sides and I was through the downwind section. The two sidewind legs were not too bad at all though a little tippy, but I really had a lot of trouble upwind, as there was so much board out of the water ( and I'm an old fat fart
) IT wasn't tippy but in the strong wind (30 Knots) on the last marker I stepped back and tried to pivot turn it around shipping post, but the strength of the wind onto the side of the dihedral hull made it impossible. I reckon the 12'6" wouldn't have that much of a problem as it sits lower in the water due to less volume. Look I'm not an experienced BOP or over paddler, but unless your'e relatively experienced I would consider it a good idea that you stick with the shorter or/and wider model until you know what you really want. 
yes i must agree the 14 foot fly is more likely suited to the 100 kg up range but still better than my glide which i had for 2 years prior
