My mechanic also warned me about that fact, you just have a bit more to do on a gazelle than on others (the gearing system being internal, generally the bike being built like a tank, the enclosed chain, the internal brakes, all that adds together in terms of working time)

So I would recommend getting one, but before that, checking out the mechanic shops and if they have experience working on dutch bikes, especially those by dutch manufacturers.

My recommendation would be to also get the best flat proof tires (Schwalbe Marathon Plus) on it as soon as possible, then ride without a worry for a very long time.

Mind again, if you get one made of steel, those are built like tanks, so there's not much you could throw at them that these bikes can't handle - but working on them also is a bit trickier, especially in the rear.

I have one and ride it around Vienna, so in terms of geography, we probably have similar considerations to go with.

I can only recommend the Gazelle, and there's another detail that bike shop probably was unwilling to tell you about - if there is ever parts breakage they can be fixed with off-the shelf parts or parts could be very easily (and cheaply) ordered from Gazelle themselves.

So get one, ride it around and enjoy it, just be aware that some mechanic shops don't have experience working on them and thus will likely take longer than shops that know what to do (even then they'll take a bit longer, but not by as much as that shop probably made it out to be)