There was a period of time near the end of the original Fisher labs company existence when the calibration procedures were changed to save costs. Fisher admitted that and that they were putting out subpar CZs. First Texas corrected that and returned the more time consuming (costly) calibration procedures to their processes. I believe it was Dave Johnson who posted about it, although I'm not positive it was Dave who posted, I'm not finding the post right now in searches. Combine that the CZ3D and CZ21 are still in production and still some of the deepest seeking detectors around, with First Texas owned Fisher Labs reputation of excellent customer service, and that adds up to a place to feel confident that they have solved the issues that happened when Fisher was going bankrupt.