Yes you can do it but from what I hear without being a big company your chances of not being blacklisted are high. I wouldn’t bother personally.

Linux Live cd to mount the Windows partition and see what is going on (if Windows won’t voot)

Hard drives performance is never as good as SSD or even ISP. Give it a break, it’s mechanical, not solid state.

Raid parity calculations take time too, don’t underestimate the impact on performance of keeping your data safe.

Snapraid is a good solution if you can schedule your backups as it is like raid, but not continuous.

My suggestion mirrors more of the above, download to ssd then move to hdd afterwards.