i have ta alu covers and no original air filter. The pcv valve is installed at the intake manifold, makes it any difference if the breather is on the left or right valvecover ?
Right side valve cover in the northern hemisphere, left valve cover in the southern hemisphere, unless your driving more west to east in the north and east to west in the south, but that is reversed in summer or winter in both northern and southern hemispheres. The only other exception is daylight vs night driving. Or what Mark Demko said.
I always have the oil fill on the driver's side, which also ends up being the cover with the breather. With stock covers anyway. Why deviate? I do suppose it is odd that the other VC basically does nothing but covering valves...