Snail Bar is great but the prices are kind of high for Bib Gourmand. You could maybe order three dishes for under whatever the price cap is these days (is there one?), but it might not be much food.
What Bib restaurants do have in common is their simpler style of cooking, which is recognisable and easy-to-eat. A Bib Gourmand restaurant will also leave you with a sense of satisfaction, at having eaten so well at such a reasonable price.