What the difference between iPhone 6 plus and 6s?

I'm buying a refurbished iPhone. I'm choosing between the 6s and 6 plus. The 6s is 365 dollars and 6 plus is 340. Is there a noticeable size difference? Which would you recommend?

The 6 has a 4.7" display vs the 6 Plus which has a 5.5" display.

The Plus has a bigger battery, higher resolution display as well. Could check GSMArena.com to see further breakdown of the differences between them