SSD are fast but they do have a couple of drawbacks. One, it is easier to currupt them and the other is if currupted some drives then show a reduced capacity after recovering from such curruption.
I think the best bet is a small SSD for your OS and apps and a regular HD for your files. How many files do you need lightening fast access to on a regular basis? Anything that you're working with can be copied to your desktop on the SSD.