I've had good luck modelling ferrite beads as a parallel RLC. Usually I
charcterize and extract the model myself. This way I can optimaze it over the
frequency range of interest. At one time I did get some RLC models from TDK for
some of their surface mount ferrites.
I'd probably have little fear of resonance effects if paralelling ferrites since
they are quite lossy.
Jeff Gloudemans
Delphi Delco Electronics Systems