SSDs may or may not be a worthwhile purchase for your OS installation, but the cost to use them as primary storage is quite prohibitive.
My preference while waiting for that tech to mature has been to use a pair of normal HDDs in a RAID-0 format for primary installation and storage, and a third HDD for the sake of backups.
For those not familiar, RAID is a setup where multiple discs are combined into a single logical unit. Multiple configurations exist, with their own advantages. RAID-1 for instance creates an extra copy of every piece of data stored on separate drives, and uses that redundancy to minimize data loss. RAID-0 on the other hand splits read/write data between two hard drives and uses the data transfer systems of both disks in tandem, effectively doubling the speed at which information can be loaded.
Edited: daishain on 3rd Dec, 2016 - 4:09am