That would be a difficult guess. Poly has two advantages: higher number of studios and the rooms can be wait listed only as studios while the SSR studios are part of 2BR lock-offs and thus 2BR wait lists would also be in competition for the rooms. However, there might be far more members waitlisting for Poly than SSR. Since you can have two wait-lists pending for the same time, best solution is to wait-list both and see if one comes through.