It can't be any worse than Alien vs Predator. Fuck me those two movies were horrid. I don't see how a prequel could be relevent. It's not like the chest-busting aliens need an origin story. They're aliens in space. What more could be added?
PLEASE don't even count those movies as a part of the Aliens series. Bleccchhh.
I love the first three. I was just saying in the "Inception" thread that there are plenty of action movies I've loved because I felt a connection to the characters, These films are good example of that.