I am growing 4 pluots in North Alabama. They are on their 3rd winter here. I prune them back a bit more than usual so I can use frost cloth if needed. They are still too young to product fruit but I hope after this one winter I will not need to cover and I will let the late frost do what it may. I have three different varieties so hoping they dont all flower at once.
You actually need the flowering to overlap so that they different cultivars can cross pollinate each other because they are not self-fertile. Also have to prune all the grafts so that no single one takes up all the sunlight/water/mineral and then also have to prune if you want the tree to be short like I do. peaches and nectarine are the same species just different cultivars, I can see you getting enough chill hours so no worries on that front. As for late frost, I think that whether you live in Maine/Canada or Florida late frost is always an issue. Hopefully you will get some 1st hand account of cultivars that work for your location.