If you're asking me, ours are pretty tart, even when they're purple. But, when they get black, they are somewhat sweet, with a small bit of tartness, a good raspberry flavor. They are small berries, maybe thumbnail size at most. I wouldn't call them the best raspberries I've ever had, but for wild, they're not bad.
Also, they come off the plant real easy when they're black. But, even when they're purple, they stay attached to a small stem, with their little thorns on them.
I sure wish we had more of the rasps around the farm, than the blackberries. I just prefer them more. But, there are more rasp brambles now than there was just a couple years ago. But, they're still outnumbered by prob five to one.
We are going to an orchard soon to try out some of their blueberries, rasps and blacks soon. I think one of their black rasps are Mac Blacks, along with Jewel, so I'll try to give a report on them when we go.