I just finished my bottle of Signatory UCF HP 15yo (from 1990). It still may not be the same as the one you're looking at though. Regardless, the one I had was very good. It had a good deal more peaty smoke in it than the OB does. Still, behind the peat was a lot of the honey sweetness that the OB HP is known for. It did take a while to open up, I remember when first opening the bottle, there was so much smoke up front that I though it was a bit 1-dimentional, but with some air, time, and water, many great flavors and smells emerged.
So I'd say for about $40-US it's very much worth getting.