Proxy in model VS Proxy in store

[lfs2008]

Please explain core difference between Proxy configured in model and Proxy configured in store.

Both classes have getProxy() method

When should i prefer first or second approach?

Thanks

[vietits]

You could find an answer here "The Data Package", "Proxies" section.

[lfs2008]

The problem is:
when i configure Proxy in store, attach it to grid and set store autoload:true - it works fine.
when i configure Proxy in model, attach it to grid and set store autoload:true - grid is empty.