Anandtech: Battle of the $125 SSDs
anandtech.com
anandtech.com
For a laptop it's more problematic since you can only fit one drive internally. When I upgrade my MBP (whenever the new ones come out), I'll probably put a larger SSD in it so there's some space for stuff you need to have on-drive.
As an aside -- for whatever reason, I couldn't get my optical drive to work in the enclosure provided with the Optibay. I didn't investigate too much, since it just doesn't matter to me.