[Wynand N]

Not all boats are built equal, regardless of materials used. Show me a bad builder and I'll show you a poor boat, again, regardless of material used.

Nevertheless, all boats needs preventative maintenance and repairs to keep it in mint condition. And herein lies the dilemma, some materials shows lack of maintenace worse than others. Metal will rust, perhaps ferro as well and unfortunately, this scenario is a very visible malady.
OTOH, a fibreglass with blisters, seepage or delamination problems will not attract any attention as this is not very visible apart from close inspections and haulouts....Same can be said of wood construction.

Different people have different budgets, needs etc. FerroCement is the answer to many people who believe in its merits, just as others who swears by some different materials.

In the end it all boils down to personal preferences.