It seems that one good vine of cucumbers will supply a person easily for just some fresh summer eating. It is so easy to end up with too many, but other people usually don't mind if you share them around.
I've never had a black brandywine. I will make sure to try one if I ever see one.
Brandywine is more common, also very very good. I happen to have black brandywine seeds so I plant those, I have no idea where I got them. I have a lot of seeds!