Personally I have system restored turned off and I only use my reg backup.
90% of the time when windows goes down it is because of something wrong in the registry. I also use a backup program to backup my important files to an external hard drive.
The system restore still keeps things on the same drive. If the drive dies so do the system restore. You always want a copy of your important files on a different device.
System restore is meant for the home user who doesnt really have a clue. It backups their desktop setting and a bunch of other things. So if the user changed a setting or dont like something they can put it back to the way it was before. But thats all it is really good for. Yes it can help when something installs or changes on the system and causes it to crash. But doesn't always work and gives home users a false sense that their stuff is backed up.
So it comes down to preference. For me, I know what I am doing, I dont want the space taken up on my ssd drives and system restore can slow the system down when it is accessing the hard drive. I keep my registry backed up at every reboot and I have my important files backed up the proper way. I myself, have no need for system restore.
So it is up to you to make that call for yourself.
Shane