We have rented from Cooper Paris Flats 4 times and can recommend them. Glenn Cooper lives in Paris and is responsive to any problems that arise (not that we've had many).

Whether an apartment is right for you depends on many factors: how familiar you are with life in France, how old are the children, do you plan to cook and eat in a lot, how do you plan to get around town, etc. Many have washer/dryers and that can be very handy for an extended trip (although quite unlike the kind you find in the US).

An apartment is not like a hotel at all, but is much more interesting.