Find system order for armax, oe, bj, like arxstruct

Hi, Using arxstruct command with

NN = struc(1:5,1:5,1);

and

nn = selstruc(V,0);
m = arx(z,nn);

matlab selects best model order for an ARX system, but I don't find a way to do it with other systems (ARMAX, OE, BJ). So I tried with for cycles like:

modARMAX = cell(5,5,5);
PE_armax = zeros(5,5,5);

nk = 0;

for na = 1:5
    for nb = 1:5
        for nc = 1:5
            modARMAX{na,nb,nc} = armax(data, [na,nb,nc,nk]);

               PE_armax(na,nb,nc)=fpe(modARMAX{na,nb,nc});        
         end
      end
  end

And then finding modARMAX cell element that minimizes PE_armax vector of final prediction errors, but when the system has many coefficients (like BJ) it becomes too slow. Is there a way to find right model like arxstruct command ?