The missions that the Q400 and most turboprops were designed for do not require a 450KTAS cruise speed. It doesn't go that high, so its not getting in anyone's way at cruise. It climbs quickly so it can reach its cruising speed in short amount of time and its only doing routes like EWR-BUF. Calling it slow as hell because its not as fast as a CRJ is ignorant. It's not a CRJ...its a Q400.