I hope you guys can clue me into something I'm a little ignorant about. I'm wondering about stick edgers. So far I have only used my Stihl FS80 straight-shaft trimmer to edge with. I have gathered from past discussions that "sticks" must be worth their weight in gold. While edging along concrete is it a danger to hit it with the blade? What about a yard that has never been edged? Is there a depth adjustment? Can they edge along buried vinyl around a flower bed? What about those discs that mount on string trimmers that allegedly let you easily see exactly where the string is? Does anyone used one of these?