It appears to work fine (it contains my home partition for my main machine I daily drive) and I haven’t noticed signs of failure. Not noticeably slow either. I used to boot Windows off of it once upon a time which was incredibly slow to start up, but I haven’t noticed slowness since using it for my home partition for my personal files.
Articles online seem to suggest the life expectancy for an HDD is 5–7 years. Should I be worried? How do I know when to get a new drive?
Use btrfs-convert to convert ext4 to btrfs.
NTFS is 31 years old and not modern by any standard. Avoid if you care about your data.