Checking in to this hotel is, frankly, a challenge even though the receptionist is delightful. The lobby is actually across the street from the actual rooms so you need to ring in at street level, go up, check in, go back down, and be let in to your room across the street. There are also multiple "Deco Corso" hotels at this location, so you may not be ringing in to the right reception. This is a low-level annoyance, but we were also there during the start of a heat wave when the metro workers were on strike and we had full luggage at the end of a trip (which meant lugging the bags up to reception on one side of the street and then back down and up to the rooms on the opposite side).
The room shows the signs of wear and the shower situation is weird (there is a full-length glass wall between the shower and the bed...which is probably great for some couples looking for that kind of voyeurism/exhibitionism, but definitely not great for traveling platonic friends) which makes the place feel more like a "love hotel" than a hotel.
I think this is a fine choice for a lower budget backpacking stay or for young couples high on the romance of Rome, but not great for mid-age travelers who, you know, want to shower without thinking for what that shower stage is commonly used and how clean it might really be.
The staff leave bottled water to use for the coffee machine, but do not use the coffee machine without checking the cleanliness first. Get your coffee at a cafe.