we stayed in the double non-refundable suite and were given a basement room. at first, we thought this would be horrible, however, it was very decent (size, cleanliness, etc), especially since we were only there to sleep.
there were a few issues with the room, namely the phone didn't work (staff didn't endeavour to fix it - they just said that we could use the main reception phone), and the shower leaked all over the floor.
the place was out of the way, but there are two buses that take you to the termini main train station within 10 - 15 minutes - we came home one night after midnight and it was completely safe.
the hotel is very quiet - especially in the beginning of october, and there's never anyone hanging around the bar.
the night shift guy was great and kept us happy and entertained and the bar is stocked well.
the grounds are gorgeous and the continental breakfast was lovely.
i would stay there again.

p.s. the hotel soaps (shampoo, bodywash, etc.) are great quality, although the fig smell wasn't for me.

If you are going to use a last minute agent to book this hotel then I suggest you choose another as you will be treated as second class citizens. I booked through Expedia, on arriving at hotel we was shown to a basement room, very dark and extremely small, I certainly not what you would expect from a 4* hotel. On requesting an upgrade for which we were prepared to pay for, we were told the hotel was full. Later we found out this was not true. The whole experience made sure we left our room after breakfast and did not return until we were exhausted from seeing the wonderful sights of Rome. I would not recommend this Hotel to anybody; there are far better hotels to choose from.

We rented Vespas which is by far the best way to see Rome. As a result we didn't need to be within walking distance of the central sights. We loved the hotel. Clean, bright, brand new and with a huge balcony terrace overlooking a very green treed neighbourhood. The beautiful breakfast room was in a "backyard" filled with huge pine trees.
The room was very well decorated with a flat screen TV and a modern bathroom
The staff were all wonderful, friendly and helpful (particularly Simon who was very good to us)
If you want a classy, clean, new hotel in a quiet verdant part of Rome this is perfect. There is a bus that is also easy to take to the sights
We'd go back in a flash.

We booked a room in the Hotel Prime Hotel Principe Torlonia in Rome (through Last minute.com), at a cost of 224 euros a night. On arriving, the hotel informed us of an “overbooking” & put us in another hotel which was considerably inferior. We could do nothing. The hotel denied any responsibility, as did Last Minute.com. This is doing business by cheating, tricking and lying. Don’t let it happen to you.