I have had it since v 2015. I back up my C: drive once a week incrementally and do a full backup every 5 weeks. It backs up to a mirrored 1TB pair on this system along with other selected backups from other drives and that gets copied to an offline drive periodically using file synchronizer. I pretty only have my software on C: and keep "data" on other drives because that can simply be copied using file sync. Keeping C: smaller makes images smaller. A lot of my stuff is actually spinning on more than one machine anyway (pictures, music etc) and my legacy stuff is backed up on lots of old drives.
My Desktop really just has Software on it too. My Email program and Data is on a Portable HD so I can bring it with me and plug into my Laptop when I'm away.
When I first set it up I had a Full Backup with only (unlimited) weekly Differentials after that to a 4T NAS. Somewhere along the line it stopped making Backups, It wasn't Full ...
After more reading last nite I figured my Desktop C Drive (plus Portable HD)) is ok with a weekly incremental and a new Full Backup after 5 or 6 Incrementals.
I also set up a Daily Differential Backup on several Key Folders on my Portable HD and a new Full of those after 5 or 6 Backups. I did Differential because I was reading it would be easier to Recover or Roll Back to a previous state, and that a corrupted Incremental file could mean Recovery to some points might not be possible.
I'll be keeping an eye on it to make sure it's doing what I think.
Usually if you are just backing up your "software" drive, the interval can be pretty long since most of that is static anyway. If you do have to set the way back machine pretty far back, you may see a lot of updates coming down but you seldom actually lose much. I will kick off a manual backup if I added some significant software change and it has run enough to see that it is OK. OTOH the image from a week or so ago has saved me several times when a new package, or even an "update" put me in the ditch.
I actually just realized I can Run multiple Backup Schemes... Right?
As soon as I see it is doing what I want I have a bunch of tweaking to do. Too much useless stuff (all the way back to Win 3.1) and multiple versions and copies of the same thing, and in different locations... etc.
1. If I miss a scheduled Backup time (PC off) will it run the next time I turn on? Or, the next scheduled time?
2. What does it do if it encounters an infected file?
This machine is on 24/7 but I think it will run as soon as it comes back up. I have seen backup running while I was doing other stuff. This is just an imaging program. If you have an infected file, I think it will faithfully be copied ... infected. That is important to remember if you think you have a virus. The virus will still be in that image so when you are restoring, be sure you go back far enough to predate the infection.
I keep all of my "data" on another drive that I back up selectively. That is just a simple "copy". It is the software drive that needs to be imaged because of the registry and how software is installed. I keep that as small as possible so the images are not huge.
Incremental Backup will require all the files to be fault-free to work. As nowadays large external hard disks are quite cheap, I only do full backups of my System Partition. On other partitions, i manually copy the stuff I find important to the external hdd every few weeks.