Going off on a slight tangent, I see the general standard seems to be for the Garrett pin pointers. With that said, I see there are other, much cheaper options - my question is, are the cheaper ones still functional? I don't doubt they are most likely not as up to scratch with the latest tech as the Garretts but have the cheaper ones performed adequately in the past prior to the Garretts? Or maybe they're still useable to some degree anyway? What are people's thoughts on which probes are ok?