We spent a week and a half at the Reef House (Winter 2016) and just loved it! Well appointed, fabulous views, right on the beach, solar powered, super clean. On the latter topic: house cleaned daily by friendly staff, beach front cleaned every morning -- even though we rose for sunrise most days, I don't recall ever beating the Reef House crew being out front and at work!
The new owners, Ben and Ester, are super nice and worked hard to help us with anything we needed: something for the house, use of bikes or kayaks (both available on a share basis if you're staying there), and restaurant recommendations. On the latter, Ben and Ester made many suggestions and really cared that we had a good experience -- when we came back Ben would check in to see how it went so he could give the next people staying with him the latest skinny. A simple thing, surely, but indicative of how Ben as Ester look after those who stay with them. They also had local lobster and shrimp on hand and allowed us to use the grill -- what a couple of dinners we were able to make (yum!), along with cooking multiple species of fish we caught.
We spent most of our time fishing, kayaking, exploring up the coast. We snorkeled, although not at the highlight area out at nearby reef. We paddled out to the reef twice -- its easy, perfect distance -- but it was windy and choppy enough both times we decided to just enjoy the paddle, instead. Friends report amazing snorkeling at the reef. We went many times, just closer in to shore (still great, just not as much coral and associated life).
Our only caution is just to be open minded and recall that the Xcalak area is far off the beaten path (5-6 hour drive from Cancun) -- and doggone it we assume that's why most people will want to come here! Town has several small grocery stores, but we recommend bringing a big supply from a bigger town and filling in with what's available in Xcalak. You won't find t-shirt shops or zip lines or bumper cars or para-sailing or Senior Frogs etc in Xcalak. If that's your gig, have a ball but probably don't come to the Reef House. But if you like doing & discovering things on your own--though Ben is happy to help you get fishing, snorkeling, and scuba diving guides--we couldn't recommend Ben and Ester's place more highly.