Yes, this is a great way to expand capacity and performance. If two or more Tempo-X, X4+4, X8, X4i, X4P, E4i, or E4P cards are installed to the same machine they must all have the same firmware version to avoid conflicts.
A very small number of Tempo-X SATA 4+4 users have reported a condition in which connected drives installed in an external case intermittently do not appear when their computer is booted.
To address this issue, update the Tempo-X SATA 4+4 card's firmware to version 1.0.1 or later by downloading and running the latest Tempo-X firmware updater.