It's got to be said that for something as new and fundamentally different as Storage Spaces it is rather disturbing that there is no reliable information available from Microsoft as to how it all works so we can make good decisions on if/how we use it. (See
http://social.technet.microsoft.com/Forums/en-US/winserverfiles/thread/63656ade-fe1e-4b43-9bfe-d7ae9005434f)
Everything out there appears to be based on experimentation, anecdote, marketing and old blog posts based on pre-RTM. Nothing I'm reading is inspiring confidence to move to it.
Please correct me if I'm missing a page somewhere!
EDIT: Actually, what would be useful is an online storage pool calculator where you can enter your disk capacities and play around to determine your preferred configuration.