Hi -
I've only good things to say about my SSD setup. I have the OS and some programs loaded on one SSD and the swap space, additional programs, and log files on another.
Having an SSD in place makes your entire system feel more responsive, programs load faster, and of course boot time is *much* better, even on my old SATA-II interfaces.
Things that it doesn't seem to impact (and I wouldn't expect it to) is any network access - like when your game starts and tags Steam (or other on-line platform) for verification, saved games, active game play where you're not accessing the HD, etc.
Personally, I will include an SSD on all of my future builds. However, the question of whether your *NEED* an SSD is kinda up to you.
The family really liked the impact when I re-built with the SSD some months ago.
Hope this helps.
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