Yeah 1.5deg -ve camber all round is a good handling/grip/tyre wear compromise on the Impreza, for the road. You can get -1.5deg on the front without camber bolts, but only a max of 1.0deg on the rear OEM setup - so you will have to fit those camber bolts to the rear struts to achieve the -1.5deg.

Also, corner weighting could be a good idea (although prob not really needed for recreational road driving)...

 

Cheers mate, what about front and rear toe, set to zero?

 

When the camber's altered it limits the toe anyway. Mine is set to 0 fr and rr anyway (I think), when Zen did it.

If you have too much toe-in/out, it can make the car feel nervous - even in a straight line. Just leave it upto the specialist to determine what it should be...