My Dad in North Ft. Myers has Kari, Fwang tung, and Sri Kembangan. I can get you some fruit to taste if you like.
Kari(orange) is decent and so is Fwang Tung (lighter yellow), but neither are anything special.
Sri Kembangan is sweeter and bigger with a bit of a floral aroma,I would rank it highest out of those but I would just barely call it good.
I have heard good things about Arkin but not tasted it yet. It is supposed to be one of the better varieties with firm fruit.Most other starfruit get overly soft when ripe. I have a young tree ,but no fruit yet.
There is a tree on Stringfellow road near you in the parking lot of the old Red's restaurant that some nurseries are propagating and calling Island gold, sounds like it is probably a Fwang Tung seedling better than the parent. I tasted one a few years ago but wasn't that impressed,maybe it wasn't ripe enough.
I really like Bell(orange) , it has the best flavor and sugar acid balance,still crispy when ripe, the only starfruit I have tasted that would actually be worth buying at a stand or store. My kids do not consider it tart at all,it is just not bland and insipid like some of the other varieties. I have a few ripe ones if you want to try them. My internal refractometer would guess they are pushing 20 brix if not higher with the dry weather we have been having. I am in Cape Coral close to Matlacha.