eBike technology explained

Hey everyone,

I've been looking into getting a cargo eBike for grocery runs and hauling my kid around, and I'm a bit overwhelmed by all the different tech out there! Specifically, I'm trying to understand the real-world difference between hub motors and mid-drive motors when it comes to cargo applications, especially for hills. Does anyone have experience with both on a loaded cargo bike, and can you explain which one truly handles heavy loads and inclines better? I'm thinking about a longtail like a RadWagon or a Tern GSD, and we have some decent hills around here.

Cheers!