I don't have a whole lot of experience, but I have used buckwheat a bit in the past and have read quite a bit about it here in HBT. With those qualifiers, buckwheat honey has a unique, and pretty powerful flavor. From what I've read, most people use a tiny bit in conjunction with other honeys like clover and wildflower to add a touch of buckwheat flavor, but it's not so good to use ALL buckwheat.