incrediBILL - 6:13 pm on Jan 1, 2011 (gmt 0)
Typically how big are these files you unzip and scan?
Are the SSDs strictly for temporary file scanning, not permanent storage?
If so, why do you care if they last more than a few years?
Simply replace them when it's time, and since you rent them from your host, replacing them is their problem, not yours.
Also, with the kind of operation you're running I'd assume you'll be upgrading to a bigger faster server in a couple of years anyway so it's probably a moot point.