We all know that GFCI's fail, but in my experience it has always been in the "failure to protect" mode while still delivering power (before the newer standard). Since I've become a member on the various RV forums it seems to be the norm that folks think GFCIs go bad and start to trip when they shouldn't. Personally I have never seen this that I can recall. (I have seen GFCIs where the home owner didn't understand how to reset them and thus condemned them as bad). As a side note I always replace the GFCI when on a GFCI "reset" call, it makes the person paying the bill feel better about what they got for their money and it also provides them with the latest version, not to mention the "tripped" light which helps them understand how to reset it.
Just curious how many have seen GFCIs that trip too "easily" and a new one fixed the problem?