Overall I really enjoyed staying at the Rome CIty Hostel. It's a really small place, I believe there are only 5 or 6 dorms. We stayed in a 6 bed dorm with bathroom.

Dorm was average sized, bathroom was clean and overall it was comfortable.

The staff were very friendly, and helped with any questions plus took the time to point out a lot of places on the map for us.

For the rooms with the shared bathrooms, there were two shower/toilets for use.

Breakfast included in the price from 7.30 - 10 (tea, cereal, bread, spreads). Small but equipped kitchen available for use.

The 'common area' is a few tables and chairs in between the kitchen area and reception, but it is cosy and allows you to talk to people.

Free computer available for use + free WiFi.

Checkout is 11am, towels for rent for 2EU.

Important to note a few things. There is no key for the hostel. The rooms do not lock, however lockers are provided (you will need a padlock or you can buy one from reception 5EU). To get into the building you need to buzz in, 24/7. The staff are always there so it's not too much of a problem, however some people may not be comfortable with this.

Nearby there was a pizza place, African food, cafes, pasticcerias, a post office, ATMs, tabbachi. The hostel itself is in the middle of the university district.

Bologna and Policlinico metro stations are both a 10 minute walk away. It is about a 20-25 minute walk to Termini, however there is a bus that goes from Termini to the front of the hostel (310).

For the price (22EU each p/n) this hostel was well worth the stay. It had a friendly atmosphere and was close enough to the metro that you felt connected but not too close to the dodgy area around Termini.

Nice little hostel located about 15-20 min walk from Termini station and about 45 minute walk from the Colosseum if you don't feel like taking the metro just around the corner. Friendly staff that will answer any of your questions with a smile and pretty comfortable beds (if you don't mind the occassional squeak from your neighbor). Features rooms with or without ensuites, ensuite is nice to have but has 2 bathrooms for general use. Breakfast served from 7-10am, pretty good, cereal, toast with some jam, chocolate crust, coffee, tea. Would stay here again though book in advance to get a cheaper rate.

Although it is a bit out of town center, there are 2 metro stops reacheable each in 10 minutes walk to/from the hostel.
Bed Mixed Dorm Ensuite means that in the room there is a little but clean bathroom; 6 Bed Mixed Dorm have no bathroom inside but there are 2 clean bathrooms near the reception.
Rooms are pleasantly worm in winter and funny cool in summer.
Staff (4 person - 1 girl and 3 guys) is friendly and helpful and speaks only in english (there is only 1 guy that speaks italian).
But consider this:
No Towels in Bathrooms (carry on 1 from home), no shelfs to put anything on, no floor cloth outside shower to clean wet floor.
No Luggage Storage: only a tall and tight wardrobe inside each room that could contains a backpack but no a luggage (suitcase).
No Security Lockers on hire to close wardrobe, you have to carry on 1 with you from home.
Elevator (no needs to use it because hostel is at ground floor).
NO CAR PARKING (from GoogleMap it seems hostel have a parking with a green gate but it is not its belonging). In front of the hostel there is parking with fee in the morning (all days) but free during the night (so if you stay in Rome more than 1 night every morning you have to move to another parking), otherwise you can park free in Via Tiburtina that is 10 minutes walk far from the hostel.
For breakfast it offers a little kitchen with a boiler for tea (white, green and classic tea), coffè powder no moka, chocolate powder, few packaged snacks. If you use cups you have to clean them by yourselves. Sink often clogs up. No separate collection of rubbish.

I recommend Rome City Hostel if your after a quite relaxed atmosphere.
The staff are extremely helpful and friendly.
The hostel it's self is very small, in a quite and i thought a good location. 10-15 minutes walk from Termini Station.
The facilities are clean, there are only two bathrooms, which could have been a bit cleaner. Get in quick if you want a hot shower! A minimal breakfast provided each morning and bring your own paddlock for the lockers provided in the rooms.
Make the most of the Metro, as there is a station (Bologna) 5 minutes down the road from the hostel. Where you can catch the B Line to the main sights. (8 minute ride to the Colosseum). I used this service everyday as it was so close, convenient and cheap.
There is also fantastic Gelati shop down the road where you can treat yourself to 4/5 massive scoops for just less than 3 euros!!!