fuses are pretty simple to wire in, change out when needed and safe to use...
at first glance, one may think a circuit breaker, with all the modern technology wrapped up in it would be better.... sometimes its more convenient to push a button to reset it, but seldom is it a better system. even at their best, a circuit breaker system can never be expected to be as cheap and trouble free for as long as a fused system would be... sure, the fuse may blow, and the circuit breaker may trip, but every time a fuse blows you replace it with a new one, and every time a circuit breaker trips, it can be reset.... but circuit breakers can and do fail in three different ways.
sometimes you just get a bum part that doesnt work properly after installing it, and even the best ones can only be expected to be reset for some unknown number of times before they become weak (wear out) and need to be replaced.
sometimes you will have one just stop working entirely and wont pass power thru it.... and then there is the worst failure of all, which is where the circuit breaker passes enough power so that it can be tested with a meter or test light, but does not pass enough amps to power the component properly, yet does not trip.. this can lead to damage of the component, and cause dangerous heat levels within the circuit...
good circuit breakers are built with a heat sensitive solder link inside them (a "fuse") so if it gets too hot it can melt out and kill the downstream circuit.... sometimes this happens prematurely.
the problem is that very few circuit breaker manufactures build their breakers for a damp enviroment, and even though not all boat are very damp, some definitely are.
so with a GOOD breaker built for a marine enviroment, you can expect some dependability for quite sometime, but most people seem to look for the cheapest breakers they can get and this will more often than not be a substandard installation for their boat....
when you have electrical problems with circuit breakers installed, the problem can be not so obvious and hard to pin point, where as with a fuse, it is either good or it isnt.
I have seen a couple times where a fuse is visually fine and should be good, but it wont pass power thru it, but its a quick and easy process to insert another one in its place.
a fuse system is much cheaper, simpler and more dependable and easier to repair, but if all the circuits are fine and perfect, installed with quality parts and things are carefully kept in order, there should be no issues with either system for a long time.
I prefer a nice compact, easy to see/inspect fuse panel installation over circuit breakers, for all the reasons listed above.