Our son got this for his 4th birthday and a year later it is still one of his favourites. We've never actually put water into the water-squirting facilities (and I certainly would not put it in the bath with its stickers) but I don't believe that this has had much impact on the fun he's had with it, while having the happy benefit of keeping down parental stress levels.
I wasn't looking for a specific fire-fighting helicopter when we ordered this, but that aspect has added a certain element to his imaginative play. And interminable questions about how this sort of helicopter might function around real fires!
Be warned that there is some assembly required and this is sometimes best done before presenting it to an eager pre-schooler.
Like all Playmobil, it's not cheap but it does withstand a fair amount of punishment. Having said that, after coming on holiday with us, one of the rotor blades snapped after landing up under a suitcase and I was thankful to discover that replacements are available and at a fairly reasonable price from Playmobil's website. (Where you can also obtain a helicopter without all the fire-fighting gear if that's what you're really after!)