Recently IGN has conducted a PS3 hard drive speed test. The summary of their experiment is that when used in a PS3, solid state technology produces a very marginal improvement over traditional hard drives.
So for now, just go for a cheap hard disc drive for your system if you want to upgrade it.
To quote: To put it simply; when used in a PlayStation 3, solid-state technology produces only a marginal improvement over traditional hard disc drives. While the results varied greatly by application, the amount of time saved can't quite justify the expense... at least not yet.
When solid-state drives become more accessible and comparable in price to their hard disc-based brethren, we recommend you pick one up for your PlayStation 3. Until then, pick up a cheap hard disc drive for your hard drive.
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