We found this hotel via Tripadvisor- but eventually chose it due to a really positive review from a friend who'd already stayed there.
We got a coach transfer from Ciampino airport which dumps you next to the railway station on the other side of Rome town from the hotel. We decided to trek across Rome center (with baggage) to the hotel. We got our bearings this way- but wouldn't recommend it if you have a lot of luggage, as it's a good hour and a half walk across town! Don't get a taxi- traffic in Rome is appalling- take the direct metro line from the station. The metro stop is a five minute walk from the hotel at the other end. Simple!
The area surrounding the hotel is mainly residential, only two streets away from the main road that leads between Castle St Angelo & the Vatican- but nice and peaceful / safe.
You will walk everywhere in Rome.
Cross the Tiber by the St Angelo bridge and you're a 10 minute walk from the Pantheon, Navona Piazza, Campo Di Fiori etc.
Cross by the Regina Margherita Bridge and you're in Piazza Del Popolo (15 mins walk), just up the road from the Spanish Steps.
The hotel is less than 5 minutes from the Vatican and Castle St Angelo. This is a HUGE plus when you have to get up early to avoid the massive queues for the Vatican museum / St Peters.
The room we stayed in was clean and modern with great air con. What else do you want?! We only really slept there. The hotel staff were polite and helpful. All of them spoke English (which is good as our Italian is useless!) and when we arrived they supplied us with a simple map and ran through how to get to the main sites etc. The room had always been cleaned and tidied whenever we returned from out excursions.
On our first day in Rome we got caught out by the weather. A torrential downpour left us soaking wet and uncomfortable. When we returned to the hotel the receptionist obviously felt sorry for us and gave us two passes to the Pope's Audience the following morning. (Which was a brilliant experience!)
Breakfast is either downstairs in the cute breakfast room or upstairs on the roof terrace. Continental- (meaning cold meats / cheeses, scrambled egg, toast, cakes, pastries, fruit, yogurts, cereals etc.), simple but well done.
There is no restaurant in the hotel- but if you're going back to the hotel to eat: you're mad! There are hundreds of excellent restaurants around the corner or just across the river.
The same goes for the bar- it's hardly ever open- but who cares?!
We would highly recommend this hotel to others. It's pretty good compared to other 3* hotels we've been to in Europe! It's not a luxury hotel- but if you're on a budget, it's excellent.
And the wallpaper... Is interesting!

I'm so surprised by the negative feedback on here - I had a wonderful stay at the Arcangelo.

It is perfectly situated for the Vatican, a mere 15 mins or so metro ride from Termini and in a lovely, quiet, safe (or so it felt) area of Rome - quite residential (which is nice) and there are lots of little local restaurants and bars nearby.

We each had single rooms, they weren't massive, but I was more than happy as all I want when sightseeing is somewhere clean and comfortable to lay my head after a weary day! The bathrooms are superb and have fabulous showers. The roof terrace is a lovely touch - we didn't ever make use of it though as we were always out and about.

There was a mix of Italians and foreigners when we were there, mainly early to mid 30s like us.

Highly, highly recommended, fabulous value for money, friendly, helpful staff - I will definitely be back there whenever I'm in Rome.

We just returned from a nine day stay at this hotel, and could not have been happier with our choice. Friendly front desk, clean every where, room, lobby, roof terrace. Room cleaned, linens replaced daily, roof terrace an exceptional place to relax at the end of a busy day, quiet, good neighborhood. A+

It's my second time in this hotel and I can really recommend it. I think it's more a hotel for elder people - at least you don't really see a lot of young people. I've been there for business trips. They have wireless (ask for it), a TV in every room and if you're alone and just for a couple of nights there - you don't need more. The furnishure is a matter of taste. I don't like the red or green walls - but whatever - you're there to sleep and not to stay the whole day in the room - right? The personal is unbeliviable nice. They helped me with everything and they also like to have just a little chat. The breakfast is ok. (I'm not really a breakfast-girl... so don't ask me about this).. A disadvantage is, that you can't get anything to drink (at least nothing hot) or to eat after breakfast. Also the bar was never open during my stays. All in all it's a nice hotel with very friendly personal - in my opinion more for elder guests (I'm 19.. but there were really no other young people). The best of all is of course that it's very in the center. You have just a shopping street, the vatican, Tiber,... next to it! Big plus!