Best preowned ipad or mini for long plane trip

I’m traveling overseas next month on a 13 hour plane ride. What’s the best iPad or mini I can buy used or refurbished for the trip? I’d be using pixelmator and possibly scrivener. I want to organize a book and possible outline some online classes.

There are some good refurb deals out there on 2017 iPad and iPad Air 2.

If you are planning to use either of them (or any iPad, for that matter) for the whole 13 hours you’ll probably want a USB battery pack to top off the battery.

anyone have ipad mini 2 - how does it fare with current OS
I’m thinking of getting this deal on groupon

only bc carrying my ipad pro 12.2 everyday is heavy - i mainly will use as second screen at work for Youtube videos, SPotify, Twitter maybe a couple light games -

aiming for 32GB model - just wondering if its too antiquated for my needs?