What is the best way to handle multiple countries, languages, and mobile/dekstop views?

Question

I have site that will need to front stores for two countries (US, MX). Both countries need to be available in en_US and es_MX languages. There is no difference between the product offerings for the countries, only the currency and translation of the product data, including images.

The theme will be responsive but there are certain blocks the are only used in the "large" or "small" screen views so something RESS like is required. There are also certain pieces of content coming from the Catalog that will need to be different for "small" and "large" screens (in addition to language) for example "category" banner images that need to be different between "small" and "large" because of the aspect ratio.

I read this post in addition to several articles and it seems like I'll need to do the second option from the SO question:

Website:    country
Store:      small/large
Store View: translations

Will this accommodate all my requirements? Are there any additional drawbacks other than those listed in the referenced SO q/a?