@dheiny - To be honest, I am not sure which would be more appropriate - gamma-ReTheta or k-omega-v2 (I need to do some more reading !). But I believe either model would be a significant improvement over assuming fully-turbulent or fully-laminar flow models for this sort of application.
@mjosic - my understanding from the discussion below, the existing kklOmega model has some issues, in particular, growth of Laminar Kinetic energy when separation occurs, and for this reason the new model k-omega-v2 is recommended instead of klOmega.