[mathnovice]

> if I have a store with 500 products, will it pre-render the HTML (photos, etc.) for all 500 products and serve it as a static request?

You can set it up to retrieve all 500 products and render the html on the server.

> What if my store has multicurrency / multilingual versions of all these 500 pages - will it pre-render all of these combinations?

The server is making all the requests that would have been made on the frontend. So if the server knew the locale of the user it could presumably load the correct currency and language.