Following are my notes for those of the wines on your list that I have tasted.
Chateau Leoville Poyferre, St. Julien, 1995: Full bodied, this deep royal purple wine is packed with still almost searing tannins but beyond those is the balance and structure to bode very well for future development. Let this one open in the glass for an hour at this stage before trying to taste it and then look for deep black currants and earthy flavors and aromas. Give it a few more years and look for the development of berry-black cherries and overlays of cedar wood, mint and vanilla. Best starting only in 2004 or 2005 and then cellaring nicely until 2020. Score 92. (Re-tasted 15 Aug 2001)
Chateau Pontet-Canet, Pauillac, 1997: Medium to full bodied and with smooth, well integrated tannins, this deep purple wine shows attractive orange-gold reflections when held to the light. Lots of plums, black cherries, and wild berry flavors and aromas, all with just the right hints of spice. When first poured the wine seems a bit overly alcoholic, but let it open in the glass for 20 minutes and you will find a ripe, well balanced character. Drink 2002 - 2012. Score 90. (Re-tasted 6 June 2001)
Chateau Cheval Blanc, St.-Emilion, 1978: Well past its peak. As in its youth still a muscular wine but one that never developed the Cheval Blanc sense of excellence. Some black fruits here but those dominated by earthy minerals and notes of overly roasted coffee. Only for the brave of heart at this stage but most definitely not for further cellaring. Drink up. Score 80. (Re-tasted 9 May 2003)
Chateau Montrose, St.-Estephe, 1981: At my last tasting (12 Jun 2000) I suggested drinking up and quickly. Glad I did that because this once lovely wine is now well past its peak, showing not only maturity but the ills of old-age. Dark garnet in color but showing distinct brown notes and too-generous clearing at the rim. On the nose and palate an earthy-spicy overlay that hides the fruits and, whatever charm may be fading within minutes in the glass. No longer scoreable. (Re-tasted 9 Sep 2003)
Chateau Montrose, St-Estephe, 1991: Dark cherry red towards garnet, medium-bodied, with soft tannins and a generous berry-cherry personality. A good quaffer now but not much more than that and not for long-term cellaring. Drink now-2000. Score 86. (Tasted 14 Jun 1995)
Chateau Lagrange, St.-Julien, 2000: Deep ruby towards purple, this full bodied and still tannic wine has precisely the kind of balance and structure that bode well for its future. Blackcurrants, berries, and generous licorice and wood here, all on a generous and elegant frame. The wine will be ready for early drinking but will be at its best from 2005 – 2012. Score 92. (Re-tasted 14 Dec 2002)