Had an absolutely amazing time at the cave house - stayed for a few days with my girlfriend and it's even more beautiful in person than it looks in the photos.
Andrew is a great host; lots of communication before we even got to santorini, booked us a transfer from the airport, was there to help us get settled in, give us tips on things to do and places to eat all over the island, as well as being available all week (even after we moved to our next place) to give you advice if needed.
The cave house is amazing and filled with so many lovely little touches, and is naturally nice and cool away from the greek sun. It's a perfect couple-y location, but be warned that you have to go up a lot of stairs/ a steep hill to get there, so may not be best location if you have mobility issues (Pyrgos is basically a massive hill so probably not the best town all around to stay in if that's the case!).
We absolutely loved Pyrgos too - I personally found Fira and Oia (to a lesser extent) to be slightly too touristy and rammed, but pyrgos was the quintessential quiet Greek village I wanted, beautiful, easily accessible and a lovely breath of fresh air away from the hustle and bustle of the rest of the island. The restaurants are amazing too (especially penelopes!)
We really loved this place, can't recommend enough.