IMHO at this bandwidth its going to be gmC, that said, the problem really has 2 big parts - Splane definition of the filter and transistor level definition of the gmC sytem itself.
I have done the Splane in behaviorals in Cadence (Vlog AMS), and Matlab (Simulink), and Excel (!! using phasor methods)
The you got to define the gm stage, and get the linearity right, and then define the filter stages themselves.
I prefer cascaded bi-quads, easier to understand whats going on. Uses 4 gm stages.
Dont forget to define how you are going to tune the thing. Adjusting either Cap size or gm value. If the linearity is an issue, I prefer switching the capacitor values, (digital switching) and running a tuning adjust cycle fairly often. (thermal variance) On that, I like to adjust the -6dB point of the filter, because it is easy tune with an input signal, and compare it in amplitude with a Vsignal/2 version.
What else? Hmmmm.. may want to go one order higher on the filter (5 pole instead of 3 for example) because the rejection characteristics may not be quite as good as the ideal math model.
My thoughts and "learning experiences" as they say.
jerry