Is there any differences in what will be backed up between an encrypted and unencrypted Time Machine Backup?

Solution 1:

The restore time is not significantly different in my case between the two backups.

My old Synology was actually the bottleneck when compared to local USB 2 and USB 3 drives - LAN use was around 70% of max on the console (80%+ of max LAN speed is about the best I could ever get out of the Synology and I think that was fluke).

If speed is key then look to use something like Carbon Copy - I find both backups and restores faster with this than TimeMachine.