BullroarerTook said..
The Fringe "likes" being underpowered. It "hates" being overpowered. I'm 83kgs and use a Fringe 4.2 when the wind gets in the high teens. I do have to pump aggressively but once I'm up it's wonderful. (1500cm2 foil) I have a 3.5 on order for 20+ days.
Otoh, when the wind gets strong enough that I decide to switch to a fin board I don't like the sail nearly as well. It works, but is a handful. Watch the videos and Jason Diffen talks about how the CoE is "fluid". That gives it the pump ability I think but you lose the locked in feeling that we like for B&J.
The Banzai is much more of an all arounder I agree. And it's only imperceptibly heavier. But I went with the fringe for the low end and since I foil much more than fin nowadays. The Fringe pumps better and (I know this sounds crazy) it "water-starts" better when underpowered. I was lucky enough to demo them back to back for a couple weeks.
I came from Icons (5 battens) and I think they are miserable foil sails. They are so stiff that they remain flat until they have so much load on them that they fill out, then the mast pressure causes the nose of your board to dive. Then you unsheet and they go flat again. Horrible when underpowered. Very nice for OPed B&J though.
I can't comment on the combat specifically, but if it's a great B&J sail it's probably not great as a foil sail.
Having moved from exclusively NP sails to a couple of Goya fringe (5m and 4m) I can echo the statement, that it doesn't like to be overpowered.... unlike the NP sails which have much more of a wind range.
a few days ago, I foiled out to sea and into a 20mph wind line on my 5m.
I'd rigged the sail to be quite powerful..as there was very little wind close inshore.
Although I could foil, I simply found it difficult to get upwind as there was just no leech tension... and kept on burning out my rear leg to stay up on the foil.
My wife, however on a 5.2 sailworks flyer, was having a blast...and later said it was one of her best foiling sessions ever.
I came back in to the beach and added max downhaul and outhaul, and went out again.
a bit more comfortable...actually relaxed a few times, but not brilliant
After this experience, I've also invested in the duotone ratchet extensions and made a mental note to rig a much smaller fringe than I think I need.