I definitely use this feature on DG, one reason I =always= go there when researching a plant new to me. Zone 10 in California is MUCH different than zone 10 in Florida.
Maybe not so useful for many people, as what grows in southern Ohio will probably grow well in Kentucky, Tennesse, Indiana, etc., given proper soil and water conditions.
For me, many plants that grow in northern Florida will not grow well in south Florida, but at least I might have a shot. But if someone says it grows well in Sarasota or Ft. Lauderdale, I feel much more comfortable it will grow for me.
For me, at least, a decidedly useful feature!
