SGrab does have some issues. For example I've noticed that if the particular volume it tries to write to pops up a requester (for any reason, say the volume needs to be inserted), SGrab locks the system up.
Indeed, there are other nice tools available aswell, but SGrab is quite good app for AmigaOS 3.x (it has usable GUI, grabbing to jpg/png/ilbm directly, mark&grab etc).
