I too have a fair bit of Lego from when I was a kid in the 60s/70s that my kids play with today. It's worth noting that it was (relatively) expensive even back

I too have a fair bit of Lego from when I was a kid in the 60s/70s that my kids play with today. It's worth noting that it was (relatively) expensive even back then. My observations on the quality of my old pieces is that they are generally excellent and certainly still usable, but: - Some of the white pieces have discoloured quite noticably - Some of the white plates (but interestingly no other colours) have deteriorated noticably - The fit between pieces seems to be a lot tighter, so that prising pieces apart can be a challenge. But really it would be churlish to overstate these issues - for this stuff to still be usable after 40 years is a testament to the quality of engineering that has gone into it. We have acquired bits of the various "knock off" Lego-esque brands and the inferior quality of these is immediately apparent.