a parallel 4 link is just as good as a parallel 3 link they are virtually the same minus one upper link
bolth also share the same adjustable rods and locations
both need panhard bars for lateral stiffness.
now if your talking about a triangulated 4 link verses a 3 link i would say the 4 link is better due to its freedom of movement and its lack of a panhard for simplicity
there is a lot more to consider when doing a link suspension this is just a short way to give my opinion on your specific question.