My husband and I had a lovely stay at Marine's. It is a cozy studio with a good layout, so it doesn't feel cramped at all. Super comfy bed and great hot water. All the amenities needed to enjoy a meal at home, make coffee and tea in the morning, and relax after a long day exploring the city. The location - right down the street from the Pantheon - is excellent. Lots of cool bars and restaurants with locals in the area. I was concerned it might be noisy at night, as there is a restaurant right downstairs, but it was surprisingly peaceful and quiet. We slept like babies! Also felt very safe walking around there late at night.
It is an older building, so you can expect a little noise from neighbors etc, but we found it a very respectful and comfortable building and didn't have any trouble. Marine was very friendly and responsive. Would absolutely stay again another time!