I'm giving this a 4 start rating based on the 1st episode only, its still very new with a lot of mystery and no doubt answers will come, La Brea has a strong Lost vibe combined with shows like Terra Nova and Primeval. I wouldn't agree with other google reviews that is the same as manifest, with Manifest you have no idea what's going on but in La-Brea by the end of the first episode its pretty clear what's happened to the people.
La Brea gets of to a very quick start there is almost no build up which i though was a good starting angle, given the type of show it represents i long intro would have been a bad choice. Special effects for the most part are looking pretty good so far not unexpected as this is the most expensive show to be created since Spielberg's Pacific.
Yes i am expecting big things from this show but will it deliver?
Honestly all i can say is that it is early days yet, this has great potential to be a winning show with multiple seasons or be cancelled after just one. If this is to be a success they need to ensure they don't make the same mistakes they did with Terra Nova and wait to long to get to the heart of the story.