2008 was as good as anything from the AOC, so I'm a believer. I especially liked the style, restrained, with a lovely, red-fruited profile. I think it has room to grow, though the back-label claim of twenty years in a good vintage seems pretty optimistic in the absence of a track record. The 2010 had good density and texture, but it was pretty shut down the times I tried it.
I have not been happy with the handful of St. Cosmes I've had lately.