Detector designs,, failures, and factory service:
57 years of owning and using hundreds of detectors of most brands from USA as well as Minelab and XP and one or two others. The more we are supposed to 'progress' it seems I have encountered more glitches or failures with both circuitry design as well as build-quality components.
I am more of an analog guy and miss the days when more quality knobbed controla were used, and good toggle-switches, too. Since 2006 I have owned a lot of T2's and a few F75' and never had an issue with the one toggle, one button and two knobs they use. I love the knob controls on the F5 and never had a problem with their pushbuttons. Had three F44's, and never had a switch problem.
However, I did have tactile switch issues with an early-release Euro Tech Pro, and tactile switch problems with an F70/Patriot, as well as a late version Omega 8000. My cost to FTP for repair? Shipping, that was it.
So far as switch / control issues, I have had more with FTP branded models, and most in just the past dozen years, but in all cases they resolved the problems w/o charge.
One thing I noticed, with both new and used models, was that the tactile switches might not like frequent use, and they seem a bit fragile such that a gentile press works, but a lot of hard presses on some of those switches might be a cause for a shorter function-life.
I like the F44 and a few other FTP models, but prefer more knobs and/or less stuff to go wrong. My top two favorites are the F75/T2 package and controls, and the F5.
Monte