R410 is not a better product. The change is specifically due the ozone depleting properties of R22. R410 is currently probably the best of the subsitute refrigerants ( there are many) in terms of efficiencies. It is not a casual changeover, due to the complete incompatibility of the oils in the two systems, and the fact that it runs at significantly higher system pressures, and an R410 condensing unit may need a 50% larger ampacity circuit.