From your point of view, the value (performance versus price) of SpectreRF would probably be rather low. The reason is that SpectreRF has many features that are very useful for us (and others) that you, however, will probably not need at all. Examples are the ability to use frequency-domain scattering parameter data in time-domain simulations, pnoise analysis that includes mixing and sampling effects, and asserts to automatically check the maximum voltage and current ratings of components. Some of these features are described in more detail in http://www.edn.com/design/integrated-circuit-design/4390686/Developing-High-Freq..., an article to which I contributed.