We had a "National Lamppon" experience with the Hotel Diplomatic. After a long drive from Sorrento, and circling around the hotel/Rome trying to find a place to park to check in, we finally got into the hotel only to find out that they gave our room away because we got there after 12 noon and it was their "high season". We were furious with this and tried to reason with the manager, but he just kept saying "it's the high season" and to "look at our contract/voucher" (which we did 10000 times and it said nothing about giving the room away).. However, he was helpful and put us up in their sister hotel, Hotel Caprice, which was on the other side of the river near the Spanish Steps.

Stayed from 12-15th July 2008. I chose it because the price seemed reasonable, plus the reviews suggested a good location and reasonable place to stay. I have to agree, that it definitely scores well. The room was quite small, but this wasn't a problem for us. The air conditioning was essential, even for mid july, and it enabled a good nights' sleep and the ability to keep the windows closed, so cutting out any street noise (we were on the first floor facing the main street) and avoiding any insect bites...
Breakfast is a cold buffet, which is fine - but I didn't rate the coffee to highly.
As far as restaurants in the area are concerned, Pizzeria Roma is OK, Vito's seems a bit overpriced and definitely catering for tourists... Better off crossing the bridge and heading for Trattoria Buca di Ripetti, which is excellent, fairly priced, and catering more for trendy Romans rather than tourists. I have nothing against tourists, but the places that cater for them I feel are best avoided.

My girlfriend and I stayed at the Hotel Diplocatic for just over a week in early August of 2007 and had a great time. The room was decent size (comparable to any holiday inn room), had air conditioning, buffet breakfast was included, was quiet, and met all of our needs.

Great location just a few minutes walk to Castel Sant Angelo, other than that there is a bus stop 3 feet from the door, so it's simple to get anywhere in town. VERY good location.

Stayed 4 nights at this property in room 502. Room was adequete size, towels changed daily, sheets were not. Only one outlet, in the bathroom, to charge my camera and iPod. Irons are not allowed. Safe and mini frig in room. Breakfast consisted of a variety of pastries, juice, ham, salami, swiss cheese, cold cereal (but room temp milk....odd) yogurt. Staff brings coffee, but not all that quickly. Internet for guests was down the entire time we were there, and no one was quite sure where the nearest internet cafe was. Internet worked fine for the staff....

Front desk staff was very friendly and helpful. City buses and the 110 tour bus stop right outside the door. We were able to get all around the city very easily. We walked to the Vatican, the Spanish steps, and Piazza Navona. Bussed it to the Colosseum. The front desk was very helpful in telling us which bus would get us where. The restaurant next door (Proffesionalist?) was nice for coffee and pastries. The hotel staff recommends Vito's for dinner, but we prefered Clok, right across the street from the hotel.