-Molecular Biology program
-International student
-Not crazy about parties but few once in a while are cool
Better teaching? Better campus? Nicer people? 
All I know is that Penn State is higher in rank
Using Niche (https://niche.com) I was able to gather that the students at Penn State have less course related stress than students at Purdue. Both Penn State and Purdue have good courses available, but Penn State has more partying. More students return to Penn State than to Purdue. More information is available on the site.
Whichever’s cheaper for you. PSU OOS is $45k - $50k per year.
How much can your parents afford? ^isnt helping very much
From what I’ve seen, Purdue’s merit aid is better (limited personal experience).
And I’d 100% go with Purdue if it’s cheaper.