  In systems with few degrees of freedom modern quantum calculations are, in
general, numerically more efficient than semiclassical methods. However, this
situation can be reversed with increasing dimension of the problem. For a
three-dimensional system, viz. the hyperbolic four-sphere scattering system, we
demonstrate the superiority of semiclassical versus quantum calculations.
Semiclassical resonances can easily be obtained even in energy regions which
are unattainable with the currently available quantum techniques.
