Couple from Australia here and we are both first time overseas travelers. This place is perfect. If you want an idea of how central this place is, we took a walk on our first morning to get a few things from a grocery store and accidentally stumbled upon Trevi Fountain. It's only a 2 minute walk away and the Pantheon is just as close in the opposite direction. A little further away are the Piazza Navona, Spanish Steps, Sant'Andrea della Valle and the Colosseum, all within 5-10 minute walk.
Even being this central the place is still so quiet, accessible and private. Being nervous first time travelers we felt comforted by being greeted by Guido upon arrival, shown everything within the apartment and given some tips for traversing Rome. It was very reassuring to have our apartment be behind three locked doors and having a concierge present during the day. The place itself was immaculate and super comfortable and great to come home to after a busy day of exploring. Can't recommend enough.