My North Code 0 is a 2.5 ounce reaching sail on it's own furler
and has a pair of 1/2" internal kevlar luff ropes. We've had the sail 12 years and have used in extensively both inshore and offshore
most important part of setting the sail is getting enough luff tension. It has to be be very tight for effective reaching above 75 degrees apparent. The North sailmaker
who custom designed the sail for our boat told me when I asked about luff tension ' "you can not put too much tension into the luff - your winches (Lewmar 44s) are not big enough" he sailed with us a few times and always put in more luff tension that I would.