I own a DC5S and my brother owns a 05 WRX. This is all my opinion by the way.

WRX: More torque/power, interior is nice as goes the exterior, power difference more noticable due to turbo, mid-range especialy, insurance wise it'll costs more, fuel consumption will be more, handles better.

DC5S: Interior is fantastic, as well as the exterior, responds well to modifications, great on fuel, handling is awesome for a fwd and is grounded (depending how you drive), 2nd > 3rd gear theres an issue of a false shift but disappears after the engine gets warmer or can be fixed with some new tranny oil, cheaper insurance, cheaper fuel, fun car to drive. Lacks the torque but a top-end machine.

Two different cars, but two great cars. It comes down to your personal choice in the end.

Good luck!