I though I would comment on this post about the Duotone f_type 6.8 mostly because there are not many reviews from owners out there.
The only review in English I saw was from a guy who hates it :-) but I think it's because he attempted to rig it on a SDM which Duotone says you can do. I have not tried it - but I will.
I have the f_type 6.8 and I haven't had any issues rigging it on my Duotone 430 Gold RDM mast. If you follow the direction which is located in a little triangle by the lower cam it's easy. The only thing I can think of is that I would zip the cam pocket as soon as the cam is in place.
The easiest way to get the cam in place is to push on the cam from the underside of the mast (when the mast is on top on the cam in the mast pocket)
On the water it feels light and powerful and it responds well to downhaul. My recommendation is to downhaul it to the VTS mark on the sail even in light wind. Yesterday I was out in roughly 10 knots of wind and it powered me through the lulls. Later in the day the wind came up - probably to 20 knots - I trimmed the sail flat - I was still overpowered but nothing I couldn't handle.
I started foiling this year and I finally broke down and got a foil sail - I like this sail and I'm thinking of buying the f_type 5.8 also.
Here's a link to a short video of me using the sail with my SS Levitator and the SS 84 Wing: