You should really only use NTFS if you’re going to be using the drives with Windows systems.
Otherwise, either EXT4 or BTRFS will work fine, and chances are, you wont notice a difference between them for an external drive.
NTFS wasn’t designed for *nix systems, and doesn’t support the UNIX style file permissions that are used by Linux, meaning you loose any and all ability to control the permissions, users, or groups on individual files. Plus it just tends to be really uncooperative at times.
If you’re getting I/O errors on a drive, that’s somewhat concerning. You may want to test the filesystem for errors, or run a SMART test on the drive itself, if possible.
I’ve already performed a SMART test and it passed.
I’ve alread performed a chkdsk on a VM with Windows, too.
Everything appears to be okay. But, I can’t read files with I/O errors yet.
They are not important, but the problem is in the future.
I had a external SSD formatted with NTFS to exchange data, and it got corrupted. Windows was complaining, but I could still read the contents. Then I let Windows do its chkdsk and that caused the volume to become unreadable.
The current NTFS 3G driver implementation in Linux uses FUSE and is just not reliable. Perhaps the new kernel driver being prepared for upstreaming will improve matters. But that may still take a few kernel cycles.