I've tasted madiera-style wine from Crimea IIRC from the 1800s. It was in an Enomatic machine in Hedonism Wines in London. I could not say it was appreciably better than something more modern.
On the other hand, I've had a glass of tawny port from the 1970s that Chez Bruce had on the menu at one point that kicked off a fruitless search into every barrel aged fortified wine I could get my hands on to recapture. It had a caramel taste that lingered for 30 minutes or more after the last sip. Amazing stuff.
Not quite 150 years old, but I've got a bottle of Taylor's 1896 Single Harvest Port in a bonded warehouse in the UK. Not sure I'll ever find the right situation to justify partaking of its 130 year vintage.
Original title: 'Rubens Menin's "Very Very Old" Port wine'