Stayed here for six nights as part of a Groupon deal which included several activities off the property. As others have mentioned the rooms are spacious and the balconies large and perfect for viewing Volcan Arenal when it is not clouded over. The hotel is designed so that every room faces the volcano so there really is no 'bad' room, but upper floor rooms really are best in my opinion. Our first morning we literally had NO hot water - apparently we shared a water tank with the room across from us which included three 20-something girls. While that did not happen again the water pressure was never great. The breakfast buffet was not huge but contained enough to please most and there was a lady who made eggs to order. Cabs INTO town cost $5; cabs back to the hotel $4. If you want to do the Rainforest Chocolate Tour, it is only 100 meters (a little over 300 feet) from the hotel - just make sure you call from the front desk and make a reservation so you're not charged for using the phone in your room. At night the toads are all over the place so get your flashlights and cameras out...they're huge! We did not eat at the hotel other than breakfast but instead ate in town...Soda Viquez being our hands down favorite. Also, if you want to do laundry they do not have a self-serve laundry here - they charge by the piece. We took our clothes into town and paid half the price to get our laundry done.

We spent 3 nights at Casa Luna and loved every minute. The hotel is in a perfect location for anything you might want to do in the area - 2 km from the Waterfall (although up a very steep and rocky hill), a short drive from the National Park (Volcano) and a short walk into the La Fortuna town (the walk is an easy 2.5 km, we did it every day and it took just under 30 minutes). It is also far enough away from the main road that it provides a quiet, relaxing place to go at the end of a long day of sightseeing. The grounds are extremely well kept and the pool is beautifully landscaped and a great place to relax.
The rooms themselves are spacious, very clean and have great Air conditioning that keeps things cool. Each room also has a balcony that has an amazing view of the volcano. What more could you want!? The staff at the hotel are very helpful and breakfast was a nice selection of fresh fruit, eggs, rice & beans, plantains, bread and more. We too were referred to Wilson the taxi driver, who we highly recommend and gave us some great dinner suggestions!
Walking by many of the other hotels in the area, we were very happy with our choice of Casa Luna and would definitely stay there again.

We stayed at Casa Luna with a Living Social Deal at the end of April.
Everything was great! Perfect location to do every activity.
The staff was very accomodating and friendly. The room was very nice as well, we requested a second floor room to get a better view of the volcano.
Everything was great, loved Costa Rica!! One regret, that we didn't make part of our trip a visit to the ocean. Overall highly recommend as long as you an adventure and nature lover!
( one thing, don't leave any food out!) The ants will attack within minutes.

Also, make sure to not miss the waterfall near by. Absolutely worth the hike, we almost didn't make it over because our schedule was so jammed packed+ with activities. We ended up going at 8am when it opened, took a cab, did the hike and had the cab driver come back and get us. We had to leave a 10:30am to go rafting. So worth it!! Not to be missed!