There are 3 Talisker 20's that I know of:
Talisker 20yo 1981/2002 (62%, OB, Sherry, 9000 Bts.)
Talisker 20yo 1982/2003 'Refill casks' (58.8%, OB, 12000 Bts.)
Talisker 20yo 1982/2002 (59.7%, OB, US Release)
The first one is a big Sherry whisky and quite unique because you hardly ever see Talisker from sherrycasks. I have the pleasure of owning a bottle of this nectar and I find it great whisky (on par with the new Lagavulin 21, which also is splendid)
The second one is a more subdued expression of Talisker. No bold sherry, but a more classic Talisker, closer to the 18yo. Also really nice whisky. Don't have a bottle (yet
) but would buy it by the case if I could find it voor $100.
On a educated guess I would say that the third one is more close to the 58.8% version than the 62%, and almost certainly the 59,7% is NOT very sherried....never tasted this one though.
And I also heartily recommend the Talisker 25. Great potion and the 2006 version is the greatest of the bunch.