We had an excellent stay at Owen's house. The location is great - it's only 20 minutes to old town. Generally all Edinburgh sights are easily available by foot.
We stayed at the house with 5 people which was no problem at all - there's a big living room and also a very nice terrace to hang out. The only remark we have got is that the 5th bed - the single cabin bed - was way too small to fit an adult. It's probably fun for children to sleep in but we did not feel comfortable and took the mattress out of the cabin.