so many rf simulation types, how to choose?

i started to read about simulation packages and compare their capabilities. I want to ask, how would one to choose a method. There are so many, some tcalled transistent, moments method, harmonic balance. Also disappointing fact, that there some tweak elements must be added to make spikes to start oscillation. i want to ask, is it enough to do transistent simulation for ghz range oscillator design. also i want to know wich method is simplier to implement in some programming language.