Originally Posted by Collabora
In a shared hosting environment, the benefit of SSD does not justify the cost. The bottleneck in site delivery is the network and the client's browser. It typically takes same order of magnitude of time to render a web page than it does to download its components.
The only purpose SSD has in a shard hosting plan is as a marketing gimmick to jack up the price by promising increased performance that does not exist.
True in a shared environment FULL SSD may prove more costly than the benefit. I also agree that you do not need full SSD to get good performance BUT SSD can be manipulated in many ways to give you great performance.
Because of the cost involved, when running a shared server not everything 'must' be SSD but the more you tend to full SSD the better.
For example you may mount the SSD drive to a MySQL partition giving you blazing fast database access with SAS for your files. If the cost can allow you could also have SSD for your swap partition and things will be a lot faster.