looking for a portable external drive suggestion?

I do have an expansion slot and it is PCIe. I also have space and cable to plug into my power supply.

The LACIE drives I have checked can provide up to 5 Gb/s trasner rates with USB 3 connection.
I would have to buy a USB 3 PCIe card.

SSD drives I would guess are fastest but at a premium price.

Thank you.