sonnet inductor

I have designed a spiral inductor in my chip (CMOS Tech. using top meatl)
I want to calculate it S-parameter.
ADS or Sonnet? which is better for RFIC?
someone tell me Sonnet is better than ADS. truely?

If someone tell you Sonnet is better, why?
I think that ADS is very good . no problem for yor spiral inductor