We stayed at the Grand Flora with Marriott points, so it was great value for us. We were traveling with 2 teenagers and thus needed 2 rooms. We booked the rooms 10 months prior to our arrival and requested the 2 rooms be next to each other, if not connected. We ended up having our children's room 3 doors down and only 1 room was available when we checked-in around 3pm.
The rooms were very nice. Our children's room was standard but our room was very spacious with a little sitting area. The management even sent a box of chocolate and a bottle of wine to our room, since my husband has elite status. A very nice touch. The bathroom was also very clean and nice, bed was very comfortable. Our room came with complimentary rooftop breakfast, but our children did not get that and we were not willing to shell out 30 euros each, so we took turn to eat breakfast. The rooftop restaurant was very pleasant, with a great view. There were plenty of food but we did not find the breakfast food of very high quality. There was a swarm of ants near one of the juice dispensers, kind of disgusting over the crisp and super white linens. We ate outside at the terrace and for a second we were away to get something, a big seagull came zooming down to grab our food. So, make sure at least 1 person sitting at the table if you still want the food.
I found the location not very desirable. It is true that the hotel is near 2 metro stations. However, metro stop Barberiini is a bit of a climb back to the Hotel and metro stop Spagna is a long walk through the tunnel to/from the Spanish Steps, very quiet at night.
If we have to pay for the hotel, we probably prefer to stay a bit closer to action. I would recommend this hotel to a friend if he/she can stay with points. If they have to pay, there are other choices, provided the Grand Flora is not cheap.