West Indies might actually do well in Tests and T20's thatn the ODI's. They simply don't know how to play ODI cricket.
Their Test record especially at home has been better than their ODI's. I doubt if they will win a Test match, however I feel they will run them close. I expect the Tests to be pretty well fought provided there are no injuries to key players in West Indies.
I predict 1-1 in T20's 4-1 for SA in the ODI's and a hard fought 2-0 for the Saffies in the Tests.