Is a hard drive the best way to archive video for 20-40 years

[Dingo41]

I am trying to determine the best way to archive 8mm and Hi8 video. Since these tapes degrade over time, I have been running them through an imac and putting them on 500 gig Lacie external hard drive. It seems that hard drives dont last forever, so after period of time I need to back up the external hard drives to new external hard drives. I have 6 questions:

1) Do hard drives degrade over time similar to the was that Hi8 tapes do?

2) Each time I copy one hard drive to another, is some quality of the video/data lost?

3) with what frequency should I be backing up the hard drives-- every 5 years?

4) Is an enterprise class hard drive recommended for this. My cursory research suggests that these are muh higher quality drives than for example a Lacie external hard drive.

5) which external hard drive(and manufacturer) would you recommend. I need have about 2TB of data

6) are SSD drives optimal or are these really not a proven technology yet