Need 512 GB SSD for Mac Pro (4,1) tower
I already have a 240GB OWC SSD HD as my main start up HD. I'm looking to add a larger SSD.
Keep in mind that the SATA drive bays are limited to 300 MB/s because they are SATA 2. If you want something faster, you'd either need to create a striped software RAID out of two SATA drive bays (which really requires two SSDs of the same size), or you get an SSD that connects directly to a PCI slot (eg, the OWC Mercury Accelsior PCI Express SSD). You can see the speed difference here.