I recently had occasion to get out an old video tape. When I picked it up, it weighed almost twice the weight of present day ones. I thought it might have been a four hour tape because of its weight. It would have been recorded in the middle eighties and when I popped it in the old JVC (no-one will get that old Graham Kennedy reference) the vision was excellent. I was amazed as I expected that it would have deterioated over time. Maybe it was a really quality tape, but unlikely as I recall always shopping for blank tapes on price.