I had active ghost shrimp who decided to suicide themselves after 2 days. If you have an open tank make sure you get a lid! I learned a cheap lesson (I only got two). They are pretty awesome to have though and after I get a lid (next week) I plan to get two more and try again with less suiciding.
They do need places to hide though. My betta isn't really aggressive but he would get near the shrimp and the shrimp would freak out (they have super long feelers). I think they just confused my betta a lot. He's been looking for them around his giant rock thing since they've been missing.