Stayed here recently and have mixed feelings
Pros and cons below


PROs

All staff are very friendly and pro active. They all seem to be trying very hard to please. This is rare in Italy.

The in-room decor and furnishings, including the bathroom and walk-in shower, is of a very high standard.

The food served at breakfast is of a very high standard.

Location is good, with metro station "Barberini" a 5 to 8 minute walk away. Trevi fountain and spanish steps about a 15 walk away.

Windows CAN be opened for fresh air.

CONs

ALL the items from the breakfast buffet are COLD, and you are allowed ONE (only one !) free item from the warm cooked items from the menu. Apart from that 1 cooked warm dish, all other warm cooked items must be paid for extra. If you are below platinum status, breakfast is 45 euro PER PERSON and this also ONLY includes the 1 warm cooked item as mentioned above. Not worth it !!

The corridors/hallways are quite narrow so if 2 people meet halfway it is always a tight fit to get past. If you are both pulling luggage, then it's even more difficult.

2 days before arrival I noticed on my Bonvoy reservation list that I had be upgraded from an entry level room to a "studio suite". When I arrived I had been downgraded back to a "wonderful room". I was not impressed.

In room welcome gift was something called "happy pills" ?!

Turn down service was done at 5pm in the afternoon...while I appreciate hotels that still do this, this seems way too early.

The whole hotel feels somewhat cramped in size. Rooms and bathrooms are small. Hallways are narrow. Elevators are medium sized. The long walk on the ground floor from the elevators to the breakfast area is also down a very long and narrow corridor/hallway. Rather than feeling like a grand 5 star hotel, this feels more like a very fancy, but also small boutique hotel. I realise they are somewhat limited by the shape of the original 19th century building, but I feel like they chose the wrong type of building for this type of modern hotel.

This property is usually a lot more expensive than the Westin Excelsior and Marriott Flora which are both a few minutes walk away, and more than double or triple the price of the Regency (tribute portfolio) which is a 8 min walk away. Is this very high price for the W hotel justified ? I'm not sure that it is. Both the Westin Excelsior and Marriott Flora both feel more like large grand hotels with more decent sized rooms and better views.