Im looking at getting a metal brush blade for my FS 110R. I need to cut dense vines, high weeds, and some brush. Im looking at Stihls website and can not decide which type of cutting blade to get for what I need. I was looking at both the Steel Brush Knife, and the Scratcher Tooth Circular Saw Blade. I have no experience using a weed eater in this manner, so I am having trouble making my mind up which to go with. http://www.stihlusa.com/trimmers/blades.html I would appreciate it if those with experience could give me some advice.