Other QBCs have been less successful. The Tallaght and Whitehall corridors, for example, offer a poor service compared with that offered on the Stillorgan route. On these routes, the QBCs are incomplete and there are long sections without any bus lane which are often heavily congested. The investment made in the QBCs has not delivered many of the hoped for improvements in terms of shorter journey times for passengers. We must reconsider the issue of QBCs in terms of what can be done to improve existing corridors, which routes offer the best prospects for new QBCs and how we can make better use of road space by giving high-occupancy vehicles access to QBCs. We must also consider whether we can secure better value for money by opening up new QBCs to competition.