I can only recall a few times when I have them side by side. In the case was with Leoville las Cases, I thought the 1982 was far superior. Marvelous tasting of Leoville las Cases last night - WINE TALK - WineBerserkers In the case of Montrose, I found the 1982 a bit of a disappointment and liked the 1990 a good bit better. TN: Chateau Montrose with Mr. Herve Berland - WINE TALK - WineBerserkers
[Not on these two vintages, but one time I had just 2 vintages side by side a 1970 Lynch Bages was better than its 1982 counterpart. This really surprised me at the time.]
For wines where I have had both but at different times, I can remember liking the Lafite, Haut Brion, and Leoville Barton better from 1982, although all of these wines are close. I am trying to think of other wines where I have had both, but cannot think of any off the top of my head.
For me, 1990s are very rich and have great fruit, but they can be a bit soft (certainly the case with the 1990 LLC and Leoville Barton IMHO). Love 1982s, but you had to be more selective in 1982 as a lot of wineries were not making good wine at that time. More wineries had improved by 1990. Probably have not had enough “lesser” wines from 1990, but so many nonclassified wines from 1982 were so, so good - wines like Meyney, Gloria, Chasse Spleen, etc.
For what wines have you had head to head comparisons?