I just want some clarification.

On the homepage it says:
"This module should not be at odds with Panels Everywhere as it merely seeks to provide a site-wide panel page which takes over the $content variable in your page.tpl.php. Panels Everywhere is geared towards replacing page.tpl.php and positioning all elements of the theme using panels (Logo, site name / slogan, navigation, tabs etc..)."

So that panels_section for Drupal 7 will take over the $content for a node. So I can change the display of the node only using this.

How is this different from Display Suite?

I wanted to use panels context, selection, and variance to change the appearance of a node/entity based on certain business rules that I put forth.

I assume that panels_section can be used for that.

Second, both panels_sections and panels_everywhere create a default template. How do they work together? Do I have to disable one for the other to work?