Penguin Parallel Texts are a distinctive and somewhat complicated institution. 20 to 30 years ago I read the then available ones in French, Spanish, Italian and German. If you are looking for collections of interesting literature, then look elsewhere! You should also read the reviews of those books in languages you don't know, to get the full picture. The one on the original 1965 Italian volume is particularly scathing, and rightly so - the literature selected is as dull as dishwater. What it says is applicable to the whole series - among the original selection criteria was the requirement that the stories not have been previously translated. Well, one good reason for their not having been previously translated might possibly be that they just weren't worth it! I was sure I hadn't read the Spanish volume, which arrived in the post today. Sure enough, the first story was Borges's Emma Zunz. Yes, I had long ago read, and forgotten about, the book. Frankly, out of all the volumes I've read, the only two stories that stimulated me to read the authors further were the Beach by Robbe-Grillet and Isabel's Soliloquy by Marquez.
But there is an important upside: all of these books contain language that is kept within close limits for learners of about A-level standard, and some serious consolidation is possible using them. And my reason for buying the three Italian volumes now is simply that over the last 10 years I've concentrated on Latin and Spanish and neglected Italian badly, so, before going on to harder stuff, I thought I'd revise my Italian. So I recommend these books, on the whole, even though I only give them three stars, but try not to let them put you off literature!
*Added: Perhaps I spoke a little too soon about the language being kept within close limits. I've just read the Gadda story in the Italian book - note to Penguin: Italian interspersed with Latin is not the most useful material for someone wanting to learn Italian!