I grow the trusted Himrod. There are also new varieties came out a couple of years ago.

I purchased a Niagara grape from a local vendor but the tag on it says Freedom Farms. More importantly, the label says "Niagara SEEDLESS". But it wasn't seedless for me the first year it gave fruit (this past summer). I've been told since then that there is no seedless Niagara, but I still have the label and can post it if anyone is curious. I hope you or someone can tell me if there is such a thing as a seedless Niagara? If there is, why did mine have seeds? Is it because it is near some other varieties that crossed with it?
If in fact it can be seedless, then Niagara is certainly my response to your question because these tasted incredible! Very sweet but enough tartness/acidity to give it a lot of flavor. Also a prolific producer. You'd know better than me whether it can be seedless or not, but it darn sure is GOOD!