I usually use Veracrypt (and in the past Truecrypt) to secure my external hard drive. I've always been taught to stick to such open-source software for my disk encryption needs, since it can be verified to be doing what it claims and the open-source community can check for possible backdoors.
I recently bought a new external hard drive, the SanDisk Extreme Pro, which seems to come with a built-in hardware AES engine. I assume this would give me much faster read/write speeds than if I used Veracrypt, but it is also of course a closed source system and I would have to trust that it works as advertised. Generally, closed source enterprise level encryption tools I've seen come with certification (I think called FIPS 140-2 or something along those lines?) that those tools work as advertised, but as this is a consumer grade product I don't believe it is advertised with any certifications beyond listing that it is 256-bit AES on its datasheet https://documents.westerndigital.com/content/dam/doc-library/en_us/assets/public/sandisk/product/portable-drives/extreme-pro-usb-3-2-ssd/data-sheet-sandisk-extreme-pro-usb-3-2-ssd.pdf.
I am wondering what the best practice in this case is, and what the pros and cons of each option are. The security of my data for me is #1 and I am happy to stick to Veracrypt if in fact the built-in encryption is considered less secure. Should I disregard the built-in encryption and stick to Veracrypt or is the built-in hardware encryption considered safe to use and I'm throwing away IO speed for no reason by not using it?
I assume Veracrypt itself is probably using hardware AES acceleration techniques, is the performance from this going to be comparable?