I have around 100,000 small files which I backup every few weeks. Because they are really small, write speed to my external 2.5" USB 3.0 HDD is really slow.
In 7zip, I compressed them using Compression level: Store. That shouldn't compress data, it should only make one big file, right? I did this because transfer speed of one big file is much better than that for a lot of small files.
If there is one bad block on the hard drive, that wouldn't be a problem if I have 100k small files - some will be lost but I will have other 99%. What happens if I have one damaged block in one really big "compressed" file? Can I recover the other 99% of undamaged data from it?