A million years ago when I took the LSAT, the format had just changed, by shortening the test. Less time, fewer questions.
I did a whole bunch of the old format tests for practice, but did them on the new, shorter time limits. As a result, I found the new format to be at a relaxed pace, relatively speaking.
My point being that unless the very nature of the questions changed, the old tests are still valuable if you adapt them to your current situation. Everybody is different, but I found that nothing was as helpful as endless practice tests. Practice, practice, practice. It would be a shame to pass on perfectly good practice exams just because they are laid out a little differently.
/cool story, bro