Check reviews for the Pelican cases on Amazon. Lots of reviews on there. From what I remember, they go over the general "gotchas" to look out for as well, such as getting one with, vs without, foam inserts. That's the most important thing to pay attention to, if I remember right.
Without the foam inserts, your laptop can still slide back and forth inside the thing, which is not something I would want to happen if it was my system in there.