I have reservations at both hotels in Madird and need to make a final decision soon regarding which one to stay at. Both are recommended by RS and both are rated well by tripadvisor and bookings. I have single rooms in both places so size wise they are about the same. Hotel Gonzalo is about $30 less per night. My concern is more about location. Hotel Europa is certainly in the center of all the activities (kilometer 0) but it may be very noisy. Hotel Gonzalo is by the Prado and is less money, but is it too far away from the nightlife activities? I would prefer walking from site to site especially during the evening hours versus being on the metro (unless other single female travelers can chime in about riding the metro at night).
My husband and I stayed at the Hotel Europa on RS Best of Spain and Morocco (2012). It is just a few steps from the metro (follow the horse's tail). Another plus is there is a post office in the El Corte Inglés department store a block from the hotel. It’s down in the parking garage. We shopped for some basic food items and mailed some items home. As for nightlife, I can't say, since we didn't stay out late. Hopefully, some other single ladies can add other insight to assist you.
I stayed in a single room in Hotel Europa in February so I don't know how noisy it is at other times of the year. It wasn't noisy then with the balcony door open all night. Except for one very early morning, when they were delivering beer kegs to the restaurant downstairs.
Hostal Gonzalo is also easy walking distance (about 5 minutes) from Plaza Santa Anna, for instance, which is one of Rick's recommended tapas neighborhoods and where I've stayed before as a single traveler. It also puts you that much closer to the museums on the days you visit them. I don't think you'll find much need for metro to cover the area mapped on p. 455 or 491.
We are big fans of Hotel Europa having stayed there several times over the past years. If concerned about noise request a room on the back. We prefer the front rooms with the French balcony overlooking the street/plaza. They can be a little noisier but we don't mind because of the view and watching the street action.
Thanks for everyone's input so far. Seems like both are nice. I'm going to sleep on it and make my decision tomorrow. Just found out a friend was just over there so I'm going to pick their brain tomorrow.
If you are planning several day trips, easy access to the train station is a factor. If you are staying more than a couple of nights, $30 is a big savings. If your concern is more about getting back to the hotel after a night of revelry, a taxi certainly won't cost you $30.
We stayed at Hotel Europain July 2012 and our room overlooked Puerta del Sol. Noise was not an issue even with the austerity protests right outside. The windows are modern and quite soundproof.