I never had an Amiga die on me. One of my A500's didn't work correctly though, when I bought them (the guy only wanted to sell his A1200 (which I _really_ wanted to have) if I took three A500s with it. It booted up fine, but the keyboard didn't work. After a short while, I found out one of the keyboardpins on the mobo was gone. Easy fix if you're handy with a soldering iron.
At the moment, I'm happy with both my 1200 & 2000 (one of each as a spare). If I can find the time & money I'm thinking of really juicing up the 2000 upto its max...