We spent a weekend in December in this hotel - it is located on 3rd floor in old building, around ~50m from entrance to Vatican Museums, around ~10min walk from St. Peter's Square and around around ~20min walk from SIT Bus stop (Transfer to Fiumicino airport). The hotel is very small (6 or 7 rooms) but it provides all you need during a stay in Rome: nice, clean, well equipped and quite spacious room with clean bathroom, good sleeping bed, free wifi internet, normal breakfast and of course really great and very kind service (e.g. our flight was much delayed and we reached the hotel in the middle of night, but there was no problem with that - we get all the instructions needed, and next day a warm welcome :). Moreover we were supposed to stay there in September, but we had to postpone our stay - fortunately the staff was very helpful in this matter).
To sum up - PapavistaRelais is a good choice (good value for money) if you would like to stay for few days in Rome, in nice atmosphere, in safe neighbourhood and have all the sights not so far away from hotel...
The only cons: shower gel enough only for 1 day.