I’ve only read the first 2, I believe. I like them because they do give some back story to a couple things that are learned in the games. Won’t change the games any, but you can at least learn about the Anderson/Sanders and Anderson/Saren relationships back story from them.

The first three books of the original trilogy are quite good, I enjoyed them a lot and I think they work quite well even on their own as more action focused scifi books. The fourth one is garbage, it’s an unnecessary addition to a complete trilogy and it caused quite the controversy at the time because it got a lot of stuff wrong about the universe. The comics are fun but nothing groundbreaking, most of them cover some side stories about characters that happen between me2 and 3. I havent read the Andromeda ones but I’ve heard good things, iirc the quarian one was supposed to be a DLC that got scrapped and then turned into a book