To answer my own question, I'm thinking PS11/FCS has a slight edge in both cases. The mirror is tough for both, PTL/AdvS can attack from so many directions, but it has to guess right, wherea VI can respond, but without as many of options.
Against the field, VI is probably worse, but its really dependent entirely on the meta. The weird thing is that the better PTL Kylo is, the better VI will be, because there will be more specific counters to PTL Kylo. It not onlu gets over things like PS10 and soke PS 11 alpha strikes, but it costs less and gives you points for a real 3rd ship.