Advice please - sure my hard drives aren't performing correctly

It seems to take a long time to transfer from one hard drive to another.
Even when I'm unrar'ing files it takes longer than I think it should.

What is the best tool for checking the speed, what speed should my drives be doing and how do I fix it?

I'm on Widows 10 and both drives are - https://www.overclockers.co.uk/tosh...-64mb-cache-hdd-oem-dt01aca300-hd-027-ts.html

Do some benchmarking with hdtune.

One is around 149 MB/Sec and the other is 192 MB/Sec

The yare both definitely 3TB but HD Tune says they are 2TB!