Dan this is part of the training system trial I am doing at my vineyard with a Northeat SARE Grant.(Sustainable Agriculture Research and Education). The angles I fabricated for a total cost of about $5.00 per brace. This will potentially increase yield by 40-60%. This is a very minor expense compared to the whole picture. I will let the vineyards that grow thousands of acres for juice grow them how they wish. I am working towards increasing yield of wine grapes while maintaining equal or improving the quality.
If this system works out well, I would look at using it on all the varieties it is suited for. If not, there are other systems to investigate.