For daily driving, no. It's not worth it.
But on the track where the car is driven hard, they help provide more cornering traction since the negative camber help keep the tires vertical during hard corning (lateral grip).. allowing the car to be pushed more through the corners.
The difference is only noticeable when cornering your car at it's utmost limit in the range where the car is about to break traction.
There's really no reason for negative camber (other than clearance) if you don't track your car or if your car is too weak to even break traction.
Also, the more negative your camber is the less contact patch you'll have in a straight line..
Typically you'd want negative camber in front and close to zero camber in the rear for FWDs. This helps the car exhibit less understeer since the rear end wants to swing around.
lol I've never tracked my car so I'm only speaking from what I've learned on the interwebzz... and Gran Turismo.