Hi Danger_Zone,
It really is up to you. Purdue is a good school, but is it great? It doesn't hold the intellectual prestige that the University of Chicago holds. It doesn't take one long to figure out which school looks better on a CV.
While Purdue gives you the path of least resistance, I think you have to seriously consider which university is going to open more doors for you in your future. Not an easy choice but often times the tougher choice has a bigger payout in the end.
Something to consider.
Good luck!
Edit: Forgot to mention, I picked MAPPS for the exact reason you're worried about (last of prestige of another school accepting you). My undergraduate history advisor let me know that the school(s) attended becomes a big deal after you've attained a MA/PhD.