well its going to be different for everyone.
Consider this: these days may not come back for a while, money is nice but you'll make that during your internship and full time job post MBA. You have a plenty of time to work hard, not nearly enough to live life. I say take off even if you dont "need" to.
Go to a place you have never been, live life a little bit, visit some friends.
Youre a smart guy, youre not going to get school burnt out. Do a month, do a weekend what ever. I would be less concerned with preparing for the "mental rigors of b school" and more focused on having some fun before school starts.
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