Filesystem Performance for LUKS Encrypted Volumes?

I've been running LUKS encrypted filesystems for over a decade, with ext2/3/4, XFS, ZFS and maybe some other filesystems I've forgotten about. While I don't have any benchmarks handy, I do have a few notes to share:

The only real performance issue you have with LUKS is the encryption and decryption itself. This introduces some latency to the process and has the potential to make disk I/O CPU-bound. On older systems without hardware AES acceleration on-chip, this was a significant issue. Today, as long as you have AES-NI in your processor and a kernel from this decade, it's almost unnoticeable for moderate workloads. Better still if you have a recent (3.x+?) kernel which can do crypto in multiple kernel threads.