"If I'm wrong I'm sure someone will correct me, but...that one looks more like what I would consider a rake grapple rather than a root grapple.
The rakes have the short sweep or no "bottom" like the root grapples that have two or three feet of bottom on them, more like a bucket.
Not sure if I have my terminology right."
Your terminology is the same I use. I thought that was a rake grapple too. We don't have rocks to deal with, but the construction attachments root grapple we have is great for picking up anything I have tried to handle. We have cleaned up a lot of brush and trees with it. After looking a little more, they are a bit more than some of the other ones mentioned ($2700 for the 66"). I can say it is worht the money though. Been using it on a M9540 4wd with no breakage yet.