I support the dissenting viewpoint of wideman. The joy of staying in Paris is the atmosphere, the people, the restaurants.

Have a walk at La Defence after 20:00 hours and taste the atmosphere: depressing. At Marriot Champs-Elysees indeed you pay a fortune to have fast-food shops and tourists around the corner.

For business I often stay at the Renaissance La Defense and at the Courtyard Neuilly. Both are good hotels and indeed you easily get lounge access to Renaissance top floor. Renaissance however charges a fee in case you are not a top tier Marriott member.

I consider both Renaissance La Defense and Courtyard Neuilly overpriced hotels. The price – quality ratio is only good in case you get a fair discount or when staying for an award.

Otherwise I would recommend for Paris to leave the beaten track of 100% US atmosphere hotels. There are lots of good places to stay. Just check with HRS, the German web hotel reservation service :
http://www.hrs.de/se/7000509?KDNR=7000509.

This week I booked with them the 'Jardin de Neuilly'. The hotel is lovely in spring and summer and at walking distance from Porte Maillot and Metroline 1.