I'm running the GMC-320 Plus, a couple of years old. The tube went out due to cats playing in the window where the detector is between the window and the screen. They dug it out and pow! it hit the floor. It hit a spike to almost 400 then stopped working. I now keep the window closed. The replacement cost was pretty reasonable and replacement easy. About $40. After a couple of weeks I'm back listed as a reliable station.
