I proposed to my girlfriend (now my wife) from the sun terrace of this lovely hotel. It was a cloudless May evening and I had lured her onto the terrace for a late glass of wine. I couldn't have chosen a more romantic setting and as you can guess it went well.
The hotel couldn't be any closer to the St Peter's Piazza and if you are feeling fit you are in walking distance of most of the sites in Rome (I had swollen, bleeding feet after 4 days but it was well worth it).
The staff at the hotel are very friendly and polite (more than you can say for most "Romans" and I don't mean that as an insult but they are famous for it and boy do they live up to the stereotype).
We arranged for the hotel's car to pick us up and there it was on our arrival to Rome - no waiting around - a very polite driver waiting to take us to the hotel in style (not inexpensive but I think it was well worth the money). As the driver turned into the narrow City streets I felt as though I had just passed through a time portal - the sense of history and the grandiosity of St. Peters is awe inspiring.
The room in the hotel was very small (we didn't have a deluxe) but it was clean, well furnished and comfortable. After all, you don't go to Rome to stay in your room.
I would definitely stay at this hotel again and fully intend to as soon as my feet return to their normal size
Col

Here is the deal. Read all the reviews, note that the good ones are from folks who stayed in the larger rooms. I believe that the biggest problem is that the small rooms are REALLY small. The website suggests a bit more elbow room than actually exists.

We stayed in a deluxe suite, with our (older) kids in a triple. The front desk staff was pleasant and helpful. The dining staff may not have been outgoing, but the area was clean, and they accomodated us (arriving late one day, leaving early the next).

I don't know how often the larger balcony is open, but they opened it for the Christmas address (wonderful) and the manager even let us out for a night photo with St Peter's dome in the background while we were dressed after Midnight Mass (nearly three AM).

If the floorplan suits your needs, the staff and location are certainly a plus!

I just returned from a stay at the Residenza Paolo VI, and will never stay anywhere else in Rome. I gather from some of the reviews and photos that I was fortunate to have a deluxe room, which was comfortable, beautiful, quiet, and spotless. It had a marble floor, and a couple of lovely oriental rugs; damask drapes; and simple, but attractive, furniture. There were casement windows -- a delightful contrast to the sealed-in windows in typical modern hotels. I cannot speak for the other rooms in the hotel, but my experience was delightful. The front desk staff was incredibly helpful and charming. I felt safe (the front door is locked in the evening), and the location -- just off one side of Piazza San Pietro -- was incredible. We strolled right from breakfast over to the papal audience in front of St. Peter's. The breakfast room is particularly beautiful, and the buffet breakfast was ample and delicious. Service in the breakfast room was pleasant, but on the relaxed side. Not a big problem, as the more impatient among us could just walk a few feet and pour ourselves a cup of coffee. The view from the terrace is matchless. There are a lot of good restaurants in the area, and a taxi stand right across the square. I recommend the hotel very, very highly, and I am a frequent business traveller with high standards.

Do not be taken in by the great marketing for this hotel, pity it doesnt live up to it.
Overpriced, rooms tiny, air conditioning poor, lift archaic, terrace tiny, appears on photos much better than it actually is.

I suggest you look elsewhere unless you absolutely must be about 500yds from St Peters Square.

Breakfast is OK.
Staff helpfull