I write out my notes by hand initially only because I'll have to write my answers in the exam anyway and it helps me to retain the information more effectively than just typing.
However, I type summaries and 'executive summaries' out on my laptop, and then print them for revision. This saves time because I've already written all the things I need to know out at least twice (from school and then in my notes at home) and can quickly revise over my summaries. Of course this is in conjunction with past-papers. Notes alone don't prepare you for an exam. You wouldn't just stretch in preparation for a running race - you'd practice running multiple times before hand (sorry for the really bad analogy haha
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Everyone learns differently though, and really its not how you present the information that's the issue. The issue is whether you are learning from the way the information is presented to you. So have a go at doing both, and see which method suits you best
Sorry there's no black and white answer...from me at least haha...