I loved Franca's apartment, thanks to the delightfully hospitable touches, the interior design, the cleanliness, the helpful communications with her, the very lovely inhabitants of the building and finally as stated, the apartment really is in an ideal position for the exploration of Rome. Everything seems 15 to 20 minutes on foot away, i.e. the Vatican, Piazza Navorno, Trastevere, all are easily and best accessed by walking. Castel Sant' Angelo is practically next door and is worth the entry fee for its treasures as much as for its restaurant with spectacular views, good food and decent prices.
As a matter, the restaurants around Franca's place are all worth trying, though I'd give Vito's (our only Christmas Day option) a wide birth for being overpriced and pushy.
I recommend Franca's place without any reservations.