RE: Light but Durable lightwind Cam sail - does it exist?
I wonder if the problem has more to do with your perception of sail strength than actual sail quality. When you mention creases to you mean visible ones (that look as if the sail would have been folded), or are they actually holes in the sail?
Most sails have visible creases, and they don't fail. I think you should worry less and sail more :-)
Another remedy is to get a sail made from x-Ply. Something like the Sailworks Retro.