If they are un reliable, why does the factory use them on most cars? I never have an issue with the one in my mustang.
Me neither. Or the one in my Dad's 04 Grand Cherokee...
Ok, let's see a reference that says e-fans are AS reliable as mechanical fans!!
I've already given several references to the problems with e-fans, let's see what you can find!!
And for one more time, I keep saying LESS reliable, not UN reliable!!!
The mechanical fan on my truck went out 2 years ago and made it overheat and not pass smog (CA...
). It was only spinning slowly and you could stop it with your hand. 
I agree that trying to prevent catastrophic failure is probably a good idea (such as using fuses on electrical connections), but building backups for every damned component is just ridiculous. Lets face it-- driving a car is a gamble in and of itself.