Location-wise, it wasn't great. It was isolated with just grass and fields, with the closest shop half an hour walk away. But as you're looking for places to stay in Jeju, you probably know about Jeju's public transport (i.e. no subway, just buses) and that renting a car in Jeju is the norm when visiting the island. None of us drove so we had to take the bus. After getting off the bus, we had to walk for around 30 minutes.
If you're planning to rent a car, this place is great. It has a free parking area and it's within driving distance to some abalone restaurants. It's also close to Mazeland.
This place doesn't have a reception so you've got to let them know in advance when you're planning to check-in. In the special requests part of the online booking process, we wrote 'Late check-in, around 8PM'. On arrival, it looked like a bunch of houses and we were unsure of where to go, so we called the number provided by Expedia. The man who answered spoke very little English, but I assume he understood we wanted to check in because 10mins later, a very confused elderly woman walked out. She did not speak any English and after 20mins of her making some phone calls. We were taken to our room.
We had booked a caravan, but amongst the confusion, she took us to their Duplex Studio which was awesome, so of course we didn't complain. PS. They require you to take off your shoes before you go in the house and leave them outside, so you might wake up to some dead bugs in your shoes.