If you're going to spend an extended period in the city you may end up getting frustrated with the local supermarkets. While eating out is a joy in Salvador, shopping for food often culminated in standing uninspired in the hypermarkets. My local Perini offered a bit of variety, with Asian foods, European goods (I was in heaven after discovering a German brand of curry sauces!) and fresh bread when I wanted something different.
The fresh goods are fantastic, above all the moist and beautifully-made cakes. I recommend the imported goods for ex-pats and the cakes and bread for everyone.
It's not a place to do all your shopping but Perini is great for treats!
What to buy: Strawberry cake. Not typically Brazilian perhaps, but I've never had a slice of cake as heavenly as Perini's morango cake. I was addicted to it during my year in Salvador.
What to pay: More than average, but then the range of products is above average.
Perini was also a grocery store located in Barra, but this was closer to the shoreline facing the ocean on the south side of town. It's a lot smaller than Bompreco, but it had some interesting items and some great pastries. A little more upscale and expensive, but a good store.