....things have changed very quickly over the past few years. High quality SATA III SSDs have come down a LOT in price, while their PERFORMANCE has skyrocketed. For video work, the Samsung 850 Pro series SSDs are IDEAL and currently the best performing, and most reliable.......BLOWING AWAY traditional HDDs in speed and reliability. A close second is the much cheaper Crucial M550 series SSDs. Choose from these 2 SSDs ONLY.....they both feature controllers that are IDEAL for "incompressible data" like digital video, which means that they can read AND write close to the SATA III theoretical interface speed of 600MB/sec. Other,cheaper SSDs use "Sandforce controllers" which may give lower write speeds,or, inferior "steady state" conditions.
These SSDs DO NOT suffer from LATENCY,like conventional hard drives do, OR, " fill degradation"....where the data transfer rate of the disk gets CUT IN HALF when the disk is full. PLUS, you have to "defrag" the disks. You may view the Haswell E benchmark test results posted on this forum by Eric Bowen which shows his test machine........his drive system is a Crucial M550 SSD. Unless you need HIGH SPEED ACCESS to a MASSIVE amount of data, ( where you would employ an expensive RAID solution with HDDs ), SSDs are the WAY TO GO. With the new X99 motherboards......depending on which one you get.....you MAY be able to setup 2 of these quality SSDs in a RAID 0 for the OS, programs, and page file only,THEN, a SECOND RAID 0 for media, projects, cache files, and all else. Conventional large HDDs can then be added for archiving and backup. Using a single HDD in your workflow that is running at 7200rpm may top out at only 130 MB/sec. transfer rate....why do that to create a bottleneck when 2 SSDs in RAID 0 could be OVER ONE GIGABYTE PER SECOND !!!!