Well both that i use are no longer in production but are fine performers ---Fisher CZ-70 deep and accurate with a Garrett GTI 1500 next (of course its not as deep as the CZ-70) like the tone ID of both ==smooth well distinguished -not "fluted" got used to the sharper tones of both of these detectors after using a Tek Mark 1 for 20 years --. hopefully Garrett will produce a newer hi end model that will replace the 2500/1500