I like it as a nibble every now and then. Its really invasive here, and grows almost as fast as bittersweet vine it seems. Greenbriar has completely covered my neighbors tree, and is slowly killing it.
Really wicked thorns on those babies, not fun to get into. The roots also go deep, and these are a pain in the ass to get rid of if you're trying to clear an area.
Glad to see a few people liked them.
RE: EATING GREENBRIAR FOR THE FIRST TIME