For some reason my Indio always had sour fruits so I sold it. It did have beautiful fruit though. I have Kucle but I find it very similar to Fukushu but just a little smaller. Some say it is inferior to Fukushu but I feel like they are very close in flavor. Maybe it depends on how much heat the tree is getting while the fruit develops. I'm in zone 8 with hot summers so I get a good amount of heat here. For out of hand eating I'd prefer Kucle or Fukushu but for flavoring foods I'd use calamondin.
Not only taste is importand, but also productivity. Can you say anything about this?