This article discusses the positive impact metro cell antennas with narrow vertical beamwidth and electrical downtilt can have on heterogeneous cellular networks. Using a model of random cell placement based on Poisson distribution, along with an innovative 3D building model that quantifies blockage due to shadowing, it is demonstrated that network spectral efficiency and average user throughput both increase as vertical beamwidth is decreased and downtilt is applied to metro cell transmission. Moreover, the network becomes more energy efficient. Importantly, these additional gains in network performance can be achieved without any cooperation or exchange of information between macro cell base stations and metro cells.