+1 yeah focus your efforts on I/O, a fast scratch drive or SSD will make all the difference.
FWIW, I wanted a cooled sensor to work with in the summer months so my strategy is not so different from working with a DSLR...trying to optimise the exposure times rather than lucky imaging (for now). I think the latter scenario is where the storage becomes more of a challenge, as a set of mono files like Glen describes are not a big deal to throw around. When I import a single DSLR raw into PI it creates a 250MB colour file...a similar set of those is becoming a fair set of data
