I've never even heard of deca being attributed to site specific growth. For the most part, if not factually, no steroid exibits site specific growth for longer than it takes for the oil to dissipate.
However, those that believe in this, go for short esters or esterless gear - not long esters.
Some do believe in LR3 IGF-1 exibiting this, but that is a chain of aminos (just like GH is), not a steroid.