I'll just interject to describe how I've gradually adopted SSDs for the essential purposes.
In 2011, the size and expense made SSDs less attractive. But I saw the potential for Intel ISRT, so I bought a 60GB SSD and used it to cache a WD Black HDD. I finally bought a 512GB 840-Pro 13 months ago. On that particular system, my only needs for an HDD were limited to DVR capture and certain files I don't keep on my server. I built another system later last year.
I'd also acquired a laptop which I refurbished with a Crucial MX100, and went through the 90-day trial period of an all-in-one caching program named Primo-Cache -- from Romex software. It worked without a hitch on the laptop, enabling me to cache the SSD to RAM, so I bought a 3-PC license for it.
I'm now using it on the second of the two desktops. The boot drive is a Samsung 840 EVO, but only 256 GB right now, approximately half full. So I used Primo with another 60GB SSD to cache a 500GB driver (for starters).
Both Intel and Samsung attempted to make the public think that ISRT or RAPID were "proprietary" and you couldn't have them any other way. You had to configure the motherboard for RAID-mode with ISRT; you had to configure you motherboard and SSD for AHCI mode to get RAPID.
Primo allows you to do it any which-a-way. So I've completely abjured RAID configurations, supplementing current solutions with robust backup. I use AHCI mode -- period. Departing from my KISS-principle inclinations, I've got RAPID caching my 840 EVO, and Primo caching the HDD. That may change soon, if I choose to swap the 512GB MX100 in the laptop for the 256GB EVO -- especially. I'll simply cache the big SSD to RAM and cache the HDD to a small 40GB SSD, using the same Primo-Cache program.
I then made sure to install all new games or other software on the HDD. So far, about 75 GB are used space. And I've never had a single problem these last four or five months with Primo-Cache.