Sperry Stop Shock hgt 6120

Has anyone else had problems with this tester. I kept getting a bad ground signal checked with my sure test and everything was alright. Tried it in another newer house same thing. Thanks John

John, I have the “commercial electric” version (looks identical to the stop shock (purchased from Home Depot)), and I recently have been getting bad grounds on every plug. I was using this as a backup/double check to my ideal circuit tester. I switched back to just a normal three light tester as my double checker.