Using an SSHD (hybrid) drive for backups

I've got a fairly long in the tooth regular WD 4TB Black drive that I use for backups and I've been considering whether there'd be any benefit in getting an equivalent sized hybrid drive as a replacement. The SSD element is used to speed up the accessing of regularly used files but as a backup is writing 95% of the time I'm not sure there'd be much point or benefit in getting a hybrid.

Anyone have any experience using an SSHD as a backup drive? What are your thoughts?

Completely pointless. The only benefit of replacing the Black would be lower power consumption and probably quieter. If you are suspending the drive when it's not in use, then both those points are reasonably moot.

I'd also consider that a NAND cache on a SSHD could increase the potential for failure which is not what you really want from a backup drive.