First of all, it is hard to find - Google Street View has the wrong address (they guide you to 137 when it is really 37) so be aware of this. There is not 24 hour reception - "Nino" is there sporadically so you must arrange with him a check-in time. This can be very inconvenient if you are uncertain of exact train/travel times. Also, be aware that they only take cash and want it upon arrival - again, another hassle. I don't expect this in a major city like Rome. So, administratively it is a bit of a nightmare. Now as for the rooms go - the cleanliness is, as I rated, OK, but would certainly not pass the white-glove inspection. There is no carpet which was a relief. The walls are in desperate need of some love, and the curtains are filthy. The shower was ok, but very small - a very large person might have some difficulties here. The bed was reasonable comfortable (considering it is not a proper mattress but a base with a camping foam type thing upon it) and the sheets did appear clean. (Note, in terms of bedding all you get is a top and bottom sheet - I was quite chilly all night). The stairs leading up to the room look like the haven't been washed in years - the hotel in general needs a good scrub.
On a more positive note, the location is great. Walking distance to Spanish Steps, Trevi Fountain, and the metro.