The best thing about this hotel is its location. As others have said, opposite Notre Dame, and walkable to all the main sights. Also right on the metro and RER lines so easy to get further afeild as well as the airports and train stations.
Staff very helpful and friendly with excellent English. We enjoyed their restaurant recommendation (which is also in the Lonely Planet).
Room average side (we were in a superior room on the 4th floor) - would hate to have seen the size of a standard room!
Downsides: the elevator wasn't working for 3 out of the 4 days we were there. Luckily we're young and fit! Staff happy to carry luggage though. Also on one morning there was no hot water from 8am for 'maintainance'. We were warned about this the evening before so we new we had to get up early if we wanted a hot shower. But seeing as it's maintainance - they should have put it at a more convenient time for their guests like later in the day! We did get a lovely fruit basket to say sorry for the disruptions, but when you're paying the very expensive Paris prices, I'd expect more! Or even complimentary breakfasts.
Great bakery tucked away round the back streets behind the hotel - useful for breakfasts in the room. Rooms have tea and coffee making facilities, although we were regularly having to ask for more milk cartons (and on one day they forgot to replenish at all, so no tea or milk).
No issues with noise from the road below.
So - we would stay here again, mainly for the location and friendly staff, but may look for something cheaper nearby.