This stuff is not bad at all (actually it's still quite good), but when you hear "Signatory Vintage Ledaig 1st Fill Sherry" these days, your associations will probably be the bottlings from the fantastic 2004 vintage.
I don't know what's different about these 2005 bottlings, I don't think it's only the slightly younger age. I assume it's rather a different kind and/ or quality of sherry casks. As a result, these 2005 bottlings to me appear much more like a re-fill type of sherried Ledaig. They don't come close to the 2004's, but again, it's still good whisky.
This very bottling (cask 900150), to my knowledge, is exclusive to German whisky trader The Whisky Store.