Overall, we had a good stay at Sole d'oro. This was one of the few properties that allowed us to house 5 people in a room with a loft, which was a huge plus. I also liked that it was in Oia, away from the main shops. While there isn't that "caldera view", I much preferred that our taxi was able to drop us off at the hotel and the staff helped us carry our bag to our rooms. It's also a short 15-20 minute walk to the main part of Oia.
We were warmly greeted right away with a welcome drink. The room was a bit tight for 5 people but comfortable nonetheless. The one feedback is wishing the bathroom was bit a cleaner. The outdoor jacuzzi fits 2 and is a nice way to destress in the evening. The breakfast was also a perk because it's served in the balcony of your room. It would've been nice if there was water given for breakfast, but there is a supermarket a few minutes away which was convenient. The staff was helpful in setting up restaurant reservations by email. And at check-out, the staff gave us a few items as a souvenir, which was a sweet gesture!
Overall, a good option to stay in Oia! I definitely recommend staying in Oia if it's your first visit to Santorini.