We ended up going to Lucky's 3 times during our week-long stay. The food was excellent (pork gyros and tzaziki with pita bread). The price was incredibly reasonable (12-15 euros total for two people). While it's a tiny place and was about 85 degrees inside, we loved how fresh the food was and how good it tasted. As is the sign of a good restaurant in a tourist area like Santorini, we saw a lot of locals ordering food here.