Our stay at Mapigarden b&b was good overall, and I would book it again - it's a great value for the price.
Things I liked most:
1. Value;
2. Location - right next to a breath taking mountain, which we could see right out our window;
3. Location - close to the train station, so access was very convenient;
4. Service of the staff was great.
Three things I liked least:
1. VERY IMPORTANT: address that showed up on hotels.com website is different from the physical location. Given that Machu Picchu is a small pueblo in general, I was still able to find the correct location. However, I did spent about 30 min wondering around and asking locals for directions (which were all conflicting of course)
2. Location. Being close to the train station has both advantages and disadvantages. Local trains like to stay at the station for anywhere between 10-30 min, idling their engines. As a result, every time a train was at a station, we had diesel/engine exhaust smell in our room. It may be less of an issue on other levels, but we were on 2nd story.
3. WiFi was pitifully slow or disappear at all sometimes.