The Westin Excelsior is near Villa Borghese and subway stops are nearby. When we were there, we walked to Spanish Steps and Trevi Fountain easily. The Church of Santa Susanna is not too far and you can get tickets to Papal Audiences there. The audiences are usually every Wednesday.
We used SPG point for 12,000 per night with the fifth night free.
I agree 100% with the comments on the Westin Excelcior in Rome. We stayed there 4 nights in May and it was one of the nicest hotels we had ever stayed in. They upgraded us to a larger room on the SPG floor with a huge terrace overlooking the rooftops of Rome. I could have stayed a month in that room. They have a 6-piece bathroom: double sink, huge shower, separate tub, toilet, and bidet. Service was very friendly without being cloying. The restaurant was very good.
The hotel is only a block from the Borghese Gardens and a short walk to the Barberini Metro station and the Trevi Fountain. We never took taxis anywhere; just walked or took buses. Buses are everywhere and very convenient, with a major bus stop across the street from the Westin.
Our only problem was when checking out. For some unknown reason they rejected our credit card for payment. Fortunately, we had a second one with us or it would have been a huge problem. Since we had to catch a train, we were in a hurry so did not do anything about it at the time, but did check with the original credit card company later. They said they had no record of a request for a charge that day from that hotel. My guess is that Westin's bank bank rejected it, not ours.
This is a very lovely palace hotel, across from the American Embassy. I would definitely stay there again. As a matter of fact, I would not hesitate to stay in a Westin anywhere in Europe. I think the Westin hotels in Europe are much nicer than the Westins in the U.S.
