The one thing I am not wild about concerning fiber optic sights is that they can be fragile.
Generally the sights themselves, as long as they are not made out of plastic, are fine.
The fiber optic element on the other hand if exposed can be broken pretty easily.
I had one on an air rifle that threw the fiber optic element and had to be replaced.
One of my friends who owned a gunshop replaced several elements for customers.
It is somewhat design dependent on how exposed and how likely to damage the element is. If you loose the element many sights still work as a blank iron sight, again somewhat design dependent. You might look into getting a spare fiber optic straw of the right diameter to have in the repair parts bin just in case. Of course if you never have a problem then it is just more crap sitting there that you don't need.