Anyone using Samsung 840 EVO 1 terabyte SSD?

There's nothing wrong with the Samsung EVO SSD's other that cost (around $350 US).

If you are just swapping out your current HD for the SSD that won't be a problem.

If you are thinking a dual drive setup moving your current HD over to the optical drives location using a HD carrier. Sadly, that won't work. The problem here is the optical drives SATA port is not SATA III (6.0 Gb/s) unlike your HD ports. So the HD will not work and besides you will loose the HD's ports crash guard protection as the optical drives port does not offer it.

Because of these issues many people stick with a SSHD instead gaining the benefits of the dual functions of the drive getting the speed of the SSD and the storage space of the traditional HD.