Instant Swap Use Case - When to use?

Hi,

What is the distinct use case for the instant swap property? Is there a way to use it such that it reduces variants and instead you can bind asset variation to variables?

I’m trying to improve performance for prototypes while adhering to requirements that assets be on the same page. I started using IS property but I’m now finding it less/not useful. I’m wondering are there distinct use cases for the IS property today?

*Instance Swap