I bought a GPS12 in 1998. It worked fine for two years, when the screen went bad. Garmin sent me a refurbished unit for $60, which I used till 2008, when I bought a 60csx. I put the GPS12 on a shelf and left it there, in case I ever needed a backup GPS.
The on/off button on the 60csx started to get squishy after about a year, then it failed completely. Really poor design. I used a little wooden dowel to turn the thing on and off till even that stopped working earlier this year.
Garmin wanted $110 for a replacement, which I agreed to, mostly because I had an investment in Garmin maps that would not transfer to anything but a replacement 60csx.
So I sent in the 60csx, and got the GPS12 out of storage. It didn't work. Something with the screen again.
The replacement 60csx arrived, and soon lost its firmware. Garmin webupdater fixed that, but it kept losing firmware. I sent it back under the 90 day warranty and received my current 60csx, which has been working OK.
So, I have owned 5 different Garmins over the years, and 4 of them have failed. The fifth one is currently working, but it's only been a month. Hopefully when it breaks it will be within the 90 day warranty period.