however you mount it, it cannot have a hard end of travel stop. Move the drive in all directions, if it hits a hard stop it's no good. The screws will slap around in the holes causing shock worse than the original acceleration.
That plate with the holes in it that heve the springs on either side- What happens when the screws start banging the sides of the holes? You can't make the holes too small or it will bind, so there will be play. I vote for the foam too.
In my initial install I used little rubber grommets on the screws (screwed into the mounting holes on the bottom of the drive) and kept the screws reasonably loose so the rubber was holding the drive up. Worked fine.
Though in my new case, the drive sits in its own little removable caddy with no shock protection. No issues.
I donno about that one, it's made to dampen vibration, not provide shock protection/suspension.
My car has a hard *** ride, I'm mounting the hard drive on some foam, then I'm using an IDE cable that has the extra bar on top of the connector. I'm going to have the cables go to the drive with a nice gentile s curve in the cables so movement wont fatigue the wires. Just enough foam to take the edge off the vibration and bumps.