Three Camels is a great property. The ger's are quite comfortable and the beauty of the wide open Gobi is incredible.
Guests should keep in mind that this is an eco lodge and the location is very remote. As a result, it isn't a true "luxury" property per se. Electricity and water are limited. Guests must also share shower facilities (which are very clean). Despite these challenges, the property does a good job of making a trip to the Gobi very comfortable.
Lunch and dinner at the Lodge were excellent by local standards and given the remote location. Food quality at breakfast was quite a bit lower and options were very limited. If you want good coffee anywhere in Mongolia, bring your own!
We opted for a deluxe ger which included its own bathroom (i.e., toilet and sink). None of the gers have private shower facilities.
My only real criticism was that we found it difficult to book the property independently without signing up for a more-inclusive and expensive tour (at least during the Naadam season). As a result, the cost of visiting Three Camels was much higher than is suggested by the rates published in Lonely Planet, 1,001 Places, etc.
If you book, keep in mind that distances in the Gobi are quite far. Most local attractions require at least a one hour drive in the desert on bumpy roads. Be sure to buy water at the Lodge to take with you in the car (Lodge vehicles were not stocked during our visit). Also, know that flight schedules are limited and prone to delays. If you want to focus on the Gobi during your trip, add in extra time at Three Camels so that you won't feel disappointed if delays and / or schedules out of UB end up eating up a lot of time. You may also end up with more time than expected if there is a cancellation or delay.
Temperatures and weather change quickly and drastically. Be sure to pack for both hot and cold weather. Also, be aware that there is no mobile service at the Lodge or in most areas that tourists visit. Plan to be out of touch and enjoy it.