My husband and I stayed in Mia's place for three days. It's a great location for exploring the old town, and there are tons of shops and restaurants and the ocean within minutes. The area is definitely touristy and so some of the closest shops and restaurants are very overpriced. One of the hosts gave us some restaurant recommendations that were great.
The room is convenient for a solo traveller or couple, but it is a bit cramped - especially the bathroom. The kitchen area is shared with other guests and there's also a lovely shared rooftop patio which is a great place to relax. The street where the apartment is located is relatively quiet, and there's a parking lot within a few minutes (for a fee).
If I returned to Rethymno I probably would want to stay a bit further from the main tourist area, but if you want to be right in the center of the action, this place is definitely for you.