I've used a number of backup / copy programs overtime, but I finally settled on using Beyond Compare. Some of the recommendation has problems: usability for commands, I've written the wrong way, it can delete nonexistent files, they have time problems when source is a Linux NAS drive, and I am not 100% sure the files are copied reliably or correctly.
Beyond Compare is useful for all types of documents. I use it to compare the master directory against the backup directories. You can use different methods of comparisons - date/time, size, crc or binary comparison. It supports file filters, such as all .jpg or exclude some hidden system files. It can show a file listing and code it to show which side is the newer file, or if desired the same. You can hide the directory contents or same files. I review the differences of all the files first and if everything looks good, I might command it to update (by time) all files from the left side to the right. Using CRC or binary comparisons, sometimes I've seen files with the same names and times being different. When it is, you can double click on the file and it will bring up a new table showing the two files contents and whats different. The you can decide which is the correct photo or even if they are actually different photos with the same name. It supports text, binary, image files and others. After I do a quick file comparisons and update, I then command it to do a full binary comparison which takes a long time. I do this so I can be 100% sure the file is copied to the destination accurately. In the past, I've seen files get corrupt in time when I copy photos from computer to computer. With 40,000 photos, it may take months or years before I realize a file got corrupt. I've seen single bit error destroy the color in a band of the photo. If you look at the bit error rate for RAM or hard drive, it might be 1 in 10 to the 9th bit. Well count up all the bits for the hundreds of GB of photos I have, its amazing I don't see much more errors. I had a lot more errors when I used to have a Pentium III. Now I use an MacPro with ECC memory, and rarely seen errors, but I still do occasionally.
Occasionally, I might have files that needs to go the opposite direction because of an error I made in the past, accidentally deleted or the directory names might have changed. You can command it to make a pure mirror from source to destination, but I never want to do that if it is my archive destination drive.
I use it for backups or any copying, photos, videos or documents. I have to start using it for music because I found bad music files recently. Last I look, they have a 30 day of actual use demo, not elapse calendar, so it can last months before it expires. There is a version for Mac, Windows and I believe Linux.