Basically the Angel Eyes are just for looks, though mine or very bright with just the angels they arent enough for night driving, it just adds aggression to the car in my opinion, but some people give flack about them since they arent a stock option for a e36 or e46 so you get a lot of people criticizing them. It all depends on what you like, if you like the look go for them. be careful where you buy them though.
www.umnitza.com is where mine came from and I love them. Especially when you add some HID lights.