I am currently studying for my CWDP-303 and have been doing research extending back from CWDP-250. CWDP-250 looks more broader in the sense that it does not concentrate on design and CWDP-303 is for refined and shorten.
From looking at the practice test for CWDP 302, Practice test A reflects CWDP 250. Practice Test B for CWDP 302 is much simplistic then Practice test A.
Now looking at the practice test in the eyes of someone that has never seen the Practice test for CWDP 250 and 302, it is much more refined and simplistic, took me less then 30 minutes to complete the first test and same for the second test with a high 90% score.
I have not taken CWDP 303 yet, but from the looks of the practice test 250, 302, and 303 I am wondering if I will be going with a false sense of confidence in to take the 303 test
As is always repeated around here..
Study to the cert objectives, not just practice tests or what is in one of the books.
After that, I would be aiming for HIGH 90's on all the tests.
You will be terribly let down, if you don't pass due to one question - which may actually be the only one in a particular section from the objectives.
It has happened to me !