I don't have either tree planted but have bought and eaten both types grown in SW Florida. NS1 fruit is a little smaller, its aroma and flavor are milder. I have bought several fruit sold as NS1 from different sources, all were similar.
I expect it would have a broader appeal to most American tastes than J-31. Most NS1 plants sold here are seedlings,apparently they must be fairly true to type.
J-31 had a much stronger funkier aroma and an additional flavor element that put me off, it had a very noticeable celery taste in the background.
If it is present in unripe fruit, that might be actually be desirable assuming you want to eat it as a vegetable, but it kept me from enjoying the ripe fruit.
I have a tip for you on reducing latex, chill fruit before cutting. I would chill the fruit in a cooler or a spare fridge since the aroma will pervade your fridge. If the fruit is very aromatic,double bag it before refrigerating or freezing the cut fruit.
Most Jackfruit freezes well in my experience. The thicker the fruit pieces, the longer they seem to stay good frozen. Thin pieces maybe 2 months,thicker pieces 6 months or longer.