It's been said here before: the older they get, the likelihood increases with time that the crappy ones ended up in the trash along the way, so what's left tend to skew toward the better ones. I've still got a 1964 that I paid $1500 for probably 30 years ago, and it's one of the best Ps I've ever owned or played. Nothing about the age guarantees a good one though. It's a stack-up of variables: just like factory-mass-produced instruments of any era.