Buckwheat honey is great... if you like the smell and taste of full diapers.
LOL!
To add to that, buckwheat honey does have what's sometimes described as a "barnyard" aroma/flavor. Before getting a large amount, I'd recommend trying to find a small bottle and see if you like it. A grocery store may have it.
I've used buckwheat honey in meads before. I usually shoot for 20-25% of the total honey if I want to bring that flavor in.