Im very skeptical about using the water blades, too much of a chance of marring or scratching, especially if there is contaminants left on the surface.
One thing I wouldn't skim on is MF accessories/towels.
Yeah, I didn't have a comfortable feeling with the blade. I'd rather use a few MF towels. Maybe for the glass they would be helpful but for the whole vehicle it doesn't seem very practical to me.