If you're hoping that the zombies in this movie are the main 'dish' like the Train to Busan then you'll be heavily disappointed! The zombies in Peninsula is more like the side 'dish'. Just there to complete the 'meal'. This is my take on this movie.
However I think, it is still a good movie. More action than horror. Also, like Train to Busan the ending is a bit underwhelming.
I'll spare the details. Go watch!