...on rue de la Paix. This one is superior. It is the only high end hotel I know in Paris, so is only one data point, but my opinion is corroborated by just about everyone who reviews the hotel on FlyerTalk's Hyatt board. The buffet alone is ~ €36, and with hot items (ordered) is ~ €50. Another buffet that's excellent is at the Hyatt at CDG, but of course that's in Roissy. I don't know what it costs as I only get it when the Regency Club lounge is closed. It is cold and hot items together, and is very, very good.

Excuse me. Temporary memory failure. The Hyatt Madeleine's buffet is very, very good, too, but not quite as good as the other two above. I can't remember the price, but it is pricey.

(And seeing where you're from, I love your city and corner of Sweden. Friends in Kungsbacka.)