there are some hosting now with SSD storage........has anyone tried them ? do they really "speed up" while you are working on your site ? or is it just a gimmick ?
Using SSD is not a gimmick, but you want to know what you are speeding up. Web servers have numerous functionality serving contents and contents comes from different sources. If you are a static webpage or only dynamic at the client end and static at the server end, then the SSD is almost useless. With sufficient memory, where static web servers normally do not require a lot of memory, once the static HTML file is read from the filesystem, it will be cached in the memory for subsequent serving unless the file is changed. Such typical web servers can be more than 90% read and 10% write or could be 100% read and 0% write for content serving purposes.
If you are using a CMS such as wordpress, joomla, or other server side application which may have dynamic write onto the SSD, yes, the SSD will offer better performance compared to the plain old magnetic hard disk, but the margin will greatly depends on how often you write to the filesystem and whether there are sufficient random access to provide the extra value from the SSD compared to the magnetic hard disk. Because magnetic hard disk and also the operating system will normally have write cache, so the performance gain for SSD will be rather insignificant if there are no heavy excessive writes on the disk.
As for reading off the CMS, the rendering of the templates with the contents normally is cached by the CMS unless your CMS has heavy dynamic pages constantly changing or cannot be cached. That's where there will be more CPU usage, but not necessarily translate to READ on the disk(whether SSD or magnetic). To add on, CMS do not normally store the contents in the filesystem. They store it in RDBMS(normally), so how fast the pages are read and formed is more depending on the performance of the database, not how fast your disk reads or write. If it is a VPS server you are using and you are given access to install or run the database off your host which is running on SSD, that's where you may get more performance but still database also have query caches, hence the benefits may or may not be apparent. A lot of database operations such as sorting, grouping, joining are perform in memory and only spill into the disk for temporary files if the tables are too large to be contained in the memory, so your mileage may varies.
Without understanding how your application works and which kind of resources if requires, SSD can be a just an expensive white elephant for you. it is not gimmicky, just over-provisioned or over-spec'ed. I hope what I have responded helped you in your understanding.
